Implementing positive psychology interventions to promote students’ English speaking performance at Thanh Dong University

Speaking skills are crucial in second language acquisition (SLA) as they enable learners to communicate effectively, express ideas, and engage in meaningful interactions. Positive psychology (PP) plays a vital role in enhancing speaking performance by fostering a supportive, motivating environment that reduces anxiety and boosts confidence. Integrating PP strategies, such as those grounded in the PERMA (Positive Emotion, Engagement, Relationships, Meaning, and Accomplishment) model, promotes student engagement, motivation, and emotional well-being, all of which are essential for sustained improvement in language proficiency. This quasi-experimental study explores the impact of integrating PP strategies, based on Seligman’s (2011) PERMA model, on the students’ English-speaking performance at Thanh Dong University. Employing a mixed-methods approach, the research compares an experimental class (EC) exposed to PP interventions with a control class (CC) under conventional teaching methods. The findings revealed a significant post-intervention improvement in the EC’s speaking scores—particularly in vocabulary, fluency, and discourse management—emphasizing the implementation of PP strategies. The study also highlights the creation of a supportive learning environment, enriched through diverse thematic discussions, fostering motivation and engagement. Despite challenges, such as diverse student preferences, the study emphasizes the effectiveness of PP strategies, contributing to innovative language pedagogy.

1 Introduction

For second language acquisition (SLA), there are important academic considerations regarding students’ speaking skills. According to Wu (2023), speaking skills play a pivotal role as class discussions, presentations, and group projects depend on the students’ ability to articulate their opinions and thoughts in a clear manner. Interacting with others leads to engagement and helps develop critical thinking that is required for better understanding of subject matter as indicated by Larsen-Freeman and Anderson (2011). For instance, English fluency is mandatory when it comes to oral evaluations such as tests, interviews, or presentations within an academic assessment program. Therefore, improving English-speaking skills can greatly amplify student’s confidence in real-life situations, too. In addition, Wu (2023) claimed that the capacity to express ideas effectively is essential for different purposes including academic achievement, social interaction, critical thinking, and readiness for communication in real-life situations. This investment supports students’ acquisition of the requisite skills sets them up for success both academically and professionally. In short, speaking skills are important to educational achievement, social interaction, critical thinking, readiness for communication in real-life situations.

Thanh Dong University (TDU) is a private institution established in 2009, distinguished by its student-centric methodology and interactive educational practice. The institution’s instructional philosophy emphasizes involvement, participation, and an immersive learning atmosphere. The academic program accommodates students in several disciplines, including majors such as Law, Economics, Languages, Pharmacy, Land Management, Public Administration, and Tourism and Hotel Management, etc. The university has been trying to enhance their speaking performance; however, students encounter linguistic challenges—including vocabulary problems, grammatical issues, and pronunciation barriers—as well as other educational constraints (Nguyen, 2023). In terms of education, lack of sufficient opportunities for interactive and communicative activities involving spoken language restricts students’ exposure to authentic spoken English. Lack of structured coursework concentrating on speaking might hinder actual improvement of practical skills. Lastly, psychological barriers may be created by societal norms or expectations concerning styles of communication coupled with fear of being judged within the educational context. Cultural expectations on students may contribute to their willingness to engage in open and expressive dialog. Hence, a comprehensive approach that addresses both the linguistic competence and teaching methods that create an enabling environment for enhancing students’ speaking skills is necessary for addressing these challenges at TDU.

Positive psychology (PP) as applied to SLA might be seen as an innovating approach considering learners-whole selves (Dewaele et al., 2019). Being a cognitive model that came about due to Fredrickson’s (2009) Broaden-and-Build theory, PP has been recognized fostering learner strengths while developing their ethics and emotions. In the context of language acquisition, PP attempts to institute an atmosphere that stimulates motivation, resilience, and optimum learning experiences (Dewaele et al., 2019). Bringing attention beyond language weaknesses alone, Peterson (2006) and Rogers (2022) argued that PP interventions in English language teaching instead aim at building upon existing talents or strengths among learners in addition with encouraging growth mindset and positive attitudes toward SLA. The latter encourages active engagement, effective communication between native speakers of English, and socioemotional skills necessary for successful language acquisition. Finally, Dörnyei (2005) corroborated this integration because it entails the cultivation of well-rounded motivated and confident foreign language learners, thereby enhance both the effectiveness and enjoyment of second/foreign language education through adopting PP approaches.

While studies on PP has been extensive about perceptions, emotions, and well-being, there has not been any direct study examining how these interventions can affect language skills development. Therefore, studies attempting to assess the effects of PP strategies in improving English-speaking performance have also been limited. Again, most of the studies brought forward in this regard are concerned with feelings, beliefs, and wellbeing as opposed to specifically handling quantifiable effects from PP intervention on language outcomes. The lack of direct inquiry into how PP influences English skills is a significant gap in the research. Filling this disparity would provide educators with better understanding of how certain language learning consequences are affected by PP strategies which could enable educational institutions create better approaches and interventions when teaching English. Hence, the main focus of this study should be on speaking skills that will explore the impacts of PP intervention on language proficiency.

The decision to place PP interventions at TDU was made on this basis of enabling it to effectively address a range of students’ problems, especially in the area of English-speaking abilities. Thus, using a strength-based approach, PP offers a comprehensive framework for improving language acquisition more broadly. Additionally, by linking teaching with PP strategies and principles, positive changes were anticipated student ambition and satisfaction resulting in appropriate conditions for improved speaking performance. Therefore, PP strategies would help create an atmosphere that is conducive to better speaking results. This involved adopting a positive view of linguistic problems which reflected on the inherent strength that comes with learning languages and developing growth mindset thereby leading to being more optimistic and empowered about acquiring mastery over the language. In addition, this perspective considered learners’ performance in English-speaking.

2 Literature review

2.1 Positive psychology

Peterson (2006) advocated that PP is the study of what contributes to people flourishing or organizations performing their best. Besides, Cromby et al. (2022) emphasized that PP is to help people lead better lives. Reasonably, there are three areas of human development, including positive emotions, positive states and traits, and positive institution (Cromby et al., 2022). Thus, PP has been ranked to cover in bringing about greater and more optimistic lives for everyone. It is important to note that PP does not serve the aims of making bad situations, but rather the science of making normal life prosperous.

PERMA is a PP framework that Seligman (2011) created to talk more about what makes people happy. As shown in Figure 1, PERMA is made up of five basic parts that are thought to be essential for happiness in life. Designed by psychologist Martin Seligman, the PERMA model presents five fundamental components for well-being and happiness: Positive Emotions, Engagement, Relationships, Meaning, and Accomplishment. By encouraging emotional resilience, developing relationships, and supporting a feeling of purpose, accomplishment, and participation in significant events, every component adds to general pleasure.

Figure 1

Figure 1. PERMA model by Seligman (2011).

Another noteworthy characteristic of PERMA model is how these factors interact with each other. According to Seligman (2011), although these may be viewed separately in terms of well-being improvement, they have been proven to work best when seen together. Additionally, with this model shaping interventions on PP, it calls for a holistic approach in understanding and improving humanity as a whole which this study seeks to do by going beyond the conventional means of measuring language proficiency.

The concept of PP that has been developed as a science is aimed at increasing the well-being, motivation, and positive aspects of people, rather than discussing their weaknesses or inadequacies. Its use in the language learning scenario is not confined to the conventional pedagogical tools but rather, it helps make positive emotions, resiliency, and engagement of the learner in and out of the teaching context. Students are encouraged to promote optimism, confidence, and a sense of control, which leads to a positive and conducive environment. Beyond the classroom, PP promotes growth mindsets and self-managed learning strategies among learners, leading to long-term motivation and persistence in language practice. All these practices have an impact on the learning process of students, as they make them more willing to communicate, reduce anxiety, and make the learning process more meaningful and enjoyable, which are essential elements in the acquisition of new speaking skills and communicative competence generally.

2.2 Significance of positive psychology to second language learning

From an acquisition point of view, Dörnyei (2005) stated that one of the main determinants for success is creating a supportive environment for learners. The author claimed that through motivation and engagement, learners will naturally attain higher language skills which can only be achieved if the classroom atmosphere is encouraging enough.

It has been noted that psychological and affective dimensions are vital in teaching language effectively. PP principles are used for SLA purposes. In this regard, Oxford and Cuellar (2014) utilized Seligman’s PERMA model to examine Mexican university students’ attitudes toward learning a foreign language. The research employed the grounded-theory method to identify reoccurring themes which included achievement, emotions, meaning making and participation, intercultural and intracultural connections. All these shed light on other more delicate aspects of positive language learning experiences. In addition, to study how Canadian college students maintained their motivation and interest in a foreign language despite adversity, Chaffee et al. (2014) used quantitative design. The finding was that use of positive appraisals together with resilience were central to deriving pleasure when having difficulties with a new language.

Dewaele and MacIntyre (2014) conducted a large mixed-methods study on the emotional aspects of Foreign Language Enjoyment (FLE) and Foreign Language Classroom Anxiety (FLCA) using data from 1,746 EFL learners worldwide. Their findings revealed that FLE and FLCA are distinct emotions, each influenced by factors like age, culture, proficiency, and perceived performance. FLE arises naturally through classroom activities. Gregersen et al.’s (2014) showed students perceiving their L2 possible selves’ development among pre-service TESOL teachers’ emotional intelligence levels at an American university. The participants were helped by emotional intelligence in managing tensions as well as incorporating personal experiences in the language learning process.

Murphey (2014) demonstrated how integrating PP into classes helped Japanese students become healthier through singing together as groups. Falout (2014) demonstrated that the classroom seating arrangements can influence learners either positively or negatively. A round seating arrangement could be suggested to facilitate trust among learners by decreasing their physical distance from teachers. Gabryś-Barker (2014) carried out qualitative research among language instructors and trainee EFL instructors, respectively. It outlined strategic planning, emotional reactions, teacher’s passion, and coping strategies as the important tools for creating a positive learning environment. These studies collectively reveal that PP principles that affect the learner’s psychological environment in teaching languages. The findings indicated different aspects of teaching language with the use of Presentation–Practice –Production (PPP).

2.3 Integrating positive psychology into language lessons

PP programs in SLA, in turn, have been able to demonstrate their ability to influence the emotional states, motivation, and interest of learners, which are essential affective variables that facilitate the language learning process (Bodner, 2016; Sauro and Sundmark, 2016; Wu, 2023). The creation of the conditions of autonomy, meaningful interaction, and purpose-driven communication occurs due to the presence of good classroom facilities, which is provided by the assistance of PP practices. In its turn, it decreases the anxiety level of students and enhances confidence and interest in communication (Abdolrezapour and Ghanbari, 2021; Wu, 2023). These psychological benefits provide fertile ground for language development, enabling further engagement and resistance to language barriers.

However, even with these positive effects, the process of PP has a relatively small or inconclusive impact on measurable linguistic proficiency when it is evaluated by traditional language tests (Rogers, 2022). This gap leads to the idea that although PP is a successful way of promoting positive and encouraging learning environments, the effects it has on immediate language performance may be mediated by affective and socio-psychological processes rather than the direct acquisition of skills. Moreover, the differences in the number of studies on the intervention duration, intensity, and fidelity of implementation also pose limitations to standardizing the PP applications in SLA, which could impact the homogeneity and generalizability of findings (Bodner, 2016; Sauro and Sundmark, 2016; Rogers, 2022). These gaps suggest that there is a need to be more careful in evaluating types of assessment, which reveal the complex interaction between affective states and language performance, and longitudinal studies to determine how the psychological gains obtained by the use of PP can be converted into linguistic gains in the long run. All in all, PP interventions can be of significant use in establishing learner-centered, emotionally supportive environments that are cornerstones of successful language learning; however, their direct influence on linguistic proficiency still requires additional empirical clarification and methodological improvement.

In practical terms, PP can be operationalized in language classrooms through a range of concrete activities that map onto PERMA. For example, teachers can foster Positive Emotions by beginning speaking lessons with short “good news” rounds or success stories about recent communication experiences; they can enhance Engagement through task-based activities, role-plays, and problem-solving tasks that require sustained, meaningful use of English. Relationships can be strengthened via structured peer feedback, cooperative projects, and rotating group membership that promote trust and mutual support. Meaning can be cultivated by inviting students to discuss topics that connect English use to their personal goals, family responsibilities, and future careers, thereby positioning speaking tasks as steps toward a valued future self. Finally, accomplishment can be supported by setting clear, attainable micro-goals for each speaking lesson, using transparent rubrics, and providing opportunities for students to self-assess and celebrate incremental progress. These examples provide a pedagogical foundation for the intervention in this study, in which PERMA-aligned classroom activities are systematically embedded into the speaking syllabus.

2.4 Previous studies in Vietnamese contexts

Cutting-edge studies have explored school college students’ perceptions and properly-being in current research examining PP inside Vietnamese educational settings suggesting various factors influencing child care center services utilization (Dinh and Le, 2021). Thus, Dinh and Le (2021) aimed at developing wellbeing PERMA model—totally surveying 546 university students from colleges located in Da Nang city. These results demonstrated well-being structure, consisting of positive emotions, engagement, relationships, meaning, and accomplishment. On the other hand, Ngo et al. (2022) synthesized ideas around learning positively at Danang Architectural University as well as investigated factors affecting positivity levels among university student readers. The study covered 343 students, and significant factors in it were facilities, teaching staff, training program, student’s initiative, and student’s passion. In another study by Nguyen et al. (2022), PERMA Profiler scale was employed to assess well-being among students of the University of Languages and International Studies Vietnam National University in Hanoi who had been suffering from social isolation due to Covid-19. The research critically examined student wellbeing and differences across academic years. It studied how well-being related to its components including positive emotions, engagement, relationships, purpose and achievement. In this case the major happiness variables (P, E, R, M, A) as well as additional challenge (H) were highly correlated with general happiness score where Meaning had the highest direct association with Positive Emotions. In contrast, Negative Emotions and Loneliness showed negative connections to current happiness level meaning that more contentment is linked to higher levels of subjective happiness during the Covid-19-induced social distance caused by the pandemic. Also, loneliness decreased fun when negative feelings intervened. Moreover, Nguyen (2023) also conducted another study on students’ perceptions toward PP in English language learning focusing emotional research on fun anxiety and multicultural preferences. In addition to emphasizing Foreign Language Classroom Anxiety (FLCAS) importance by stressing its moderate levels; this test also shows that there’s a high positive relationship between foreign language enjoyment (FLE) and multicultural personality traits (MPQ).

2.5 Theoretical framework

The given research is based on the PP theoretical framework proposed by Seligman (2011), specifically on the PERMA model, which comprises five core factors that contribute to well-being: Positive Emotions, Engagement, Relationships, Meaning, and Accomplishment. The PERMA model is a holistic approach to the issue of language learning, where cognitive development is not the sole priority but the affective and social factors that require the stimulation to get a learner motivated and tougher (Seligman, 2011). This study will enhance the psychological well-being of the learners by incorporating the concepts of PP in the teaching of the English language. Consequently, this results in increased motivation, engagement, and speaking competence.

When using this framework, the research involved specific interventions that helped to develop positive emotions (e.g., gratitude practices), deep engagement with the help of interactive and meaningful speaking activities, supportive relationships with peers, linking language learning activities to the personal goals of learners and their real-life experiences, and rewarding success to reinforce the sense of accomplishment and the feeling of self-efficacy in learners. All of these interactive components of PERMA were coordinated to ensure that the classroom space was positive and supportive, both to facilitate the emotional well-being of an individual and to facilitate language acquisition (Seligman, 2011; Wu, 2023). The more one was involved, the more positive emotions and good relationships were developed, thanks to social support. Perseverance and the self-esteem that came with an appreciation of success keep motivation alive and learning significant. This reciprocal relationship was the starting point of the theoretical framework of nature in which PP interventions could comprehensively address the affective needs of learners, as well as their linguistic growth.

3 Methodology

3.1 Research design

Rogers and Révész (2020) indicate that quasi-experimental setup is often used when it is tough to randomly assign subjects. Yet the analyst seeks to measure the effect of some action. In such a study, the analyst cannot fully dictate who participates, often as a result of real-world constraints. Despite the lack of random section, these designs let researchers link cause and effect. By smartly selecting comparison groups and using statistics to control for variables that might muddle results.

The recent study used a quasi-experiment research design, which is appropriate for ethical and practical issues at TDU. The quasi-experiment lasted 12 weeks. Due to the way this research is set up and ethical concerns, random selection, which is often difficult in classrooms, is not possible. As in experiments, the variable (PP intervention designed to improve students’ English-speaking performance) may be intentionally controlled rather than left to chance. It is easy to see the precise results of PP intervention. This approach works well for the unique problems in this research and allows the researcher to assess the effectiveness of the assistance. This is a proper and beneficial approach to conduct the research, despite some challenging aspects, such as the need to monitor group differences.

3.2 Research questions

This research aimed at evaluating whether PP interventions had any impacts on students’ speech performance at TDU or not. Primarily, it tried to explore if there are any relationships between the implementation of these interventions and learners’ ability to speak fluently. PP’s goal was to give a fuller picture of individual experience by addressing difficulties and uncertainties only as well as findings that contribute to emotional states that further human development. Therefore, the research questions are addressed as follows:

1. To what extent do PP interventions influence students’ English-speaking performance?

2. What are the perceived benefits and challenges of implementing PP to students’ English-speaking performance?

3.3 Participants

The study was conducted among 53 students at TDU. Table 1 demonstrates the demographic snapshot, providing an overview of the age distribution, gender composition, and the range of participants’ experiences in studying English.

Table 1

Table 1. Demographic information of the participants in the current study.

Moreover, the data illustrate that participants have varying English learning backgrounds where some have been studying English for 6–8 years, while others started only recently. The majority of them were between 18 and 19 years, with slightly more males than females.

The present sample for the study comprises two classes consisting of a total number of 53 students who are all at pre-intermediate level. Class A, consisting of 24 students, served as the experimental class (EC), while class B, with 29 students, functioned as the control class (CC). These students come from diverse backgrounds, and they are enrolled in Basic English II using “Cutting Edge” published by Longman ELT (2013). At TDU, Basic English II course includes speaking components, listening, and reading and writing. However, for the purpose of this study, the focus is exclusively placed on evaluating and improving communicative competence during spoken interaction.

3.4 Data collection and analysis

3.4.1 Pre- and post-speaking tests

VSTEP-standardized format was used for conducting pre- and post-speaking tests in the study. It consists of three parts: social interaction, problem solving, and topic development. The time given for each candidate was around 12 min. Sample of the speaking test is attached in Appendix 2. Eventually, the research relies in VSTEP grading scale as described by Nguyen et al. (2020). It examined four areas:

• Grammar (Range, Accuracy)

• Vocabulary (Range, Control)

• Pronunciation (Sound, Stress, Intonation)

• Fluency (Hesitation, Extended Speech)

• Discourse Management (Thematic Development, Coherence, and Cohesion)

Each criterion is rated out of 0 out of 10, with lower scores (0–2) pointing to lack of control and frequent mistakes that hinder communication; mid-range scores (3–5) suggesting partial control with noticeable mistakes but generally understandable speech; high scores (6–10), representing an improvement in accuracy, complexity, fluency; and coherence with a score of 9–10 indicating close to native proficiency and few mistakes. For the analysis of speaking test results, SPSS 26.0 was used, and sample t-tests were conducted to compare the speaking performance within each group and between the EC and the CC to examine whether there are any significant differences in speaking proficiency before and after the PP interventions and making a comparative analysis between the EC and the CC.

3.4.2 Semi-structured interview

In this study, semi-structured interviews were chosen as a primary data collection instrument, where students from EC who had highest scores as well as those with lowest ones in post-speaking test were interviewed. Specifically, three students who scored high during the test were interviewed, while three others with low marks were also selected for interviews. To create an informal setting that would encourage them to freely share their experiences, these interviews took on a face-to-face format that fostered conversations.

Flexible structures are maintained in semi-structured interviews, which allow the researcher to adapt queries according to participant’s reaction (Brinkmann, 2014). This flexibility ensures that the best and most relevant information can be explored in much depth. Also, these open-ended questions enable participants to communicate their thoughts freely and thus generate highly descriptive responses. This level of understanding is very important for examining subjective experiences, as well as perceptions surrounding PP usage. Moreover, semi-structured interview dialog style ensures greater involvement of subjects while conversing with them. It also makes an atmosphere where respondents feel comfortable expressing themselves and sharing their experiences honestly thereby leading to more authentic responses. Lastly, by involving both high and low post-test scores among participants in the study supplement such views within this research strategy using a qualitative approach through the collection of rich data.

The semi-structured interview guide was designed to explore learners’ experiences and perceptions regarding the application of PP strategies in comprehensive English-speaking classes. The guide was divided into 14 open-ended questions arranged into six thematic sections: (A) General Experience with PP-based Class, (B) Effect of PP on English Speaking Skills, (C) Learning Environment and Support, (D) Motivation and Engagement, (E) Challenges and Difficulties, and (F) Suggestions and Additional Comments. The given structure provided the opportunity to thoroughly investigate what the overall participants had learned and how they had experienced their speaking ability (including vocabulary, fluency, pronunciation, and discourse organization), classroom interactions, motivational shifts, challenges, and suggestions concerning further practice.

To enhance the content validity of the interviews, the initial version of the guide was reviewed by two experts in TESOL and educational psychology who were familiar with Positive Psychology and EFL speaking instruction. They assessed the clarity, relevance, and coverage of the questions in relation to the research questions and the PERMA framework. Based on their feedback, several items were reworded or reordered to avoid overlap and leading formulations. A pilot interview with one student who did not take part in the main study was then conducted to check comprehensibility, flow, and estimated duration. Minor adjustments were made after the pilot, particularly to simplify wording and to add neutral prompts (e.g., “Can you tell me more about that?”) that encouraged elaboration without imposing particular interpretations. Several strategies were employed to strengthen the reliability of the interview data. During data collection, the same interviewer used the standardized guide and followed a consistent opening script and closing checklist for all participants. Immediately after each interview, brief field notes were written to record contextual details and initial impressions. For data analysis, two researchers independently coded a subset (30%) of the transcripts using a preliminary coding scheme derived from the research questions and the PERMA model. Inter-coder agreement was discussed in joint meetings, and discrepancies were resolved through negotiation, leading to refinement of the code definitions. The remaining transcripts were then coded using the agreed scheme. Member checking was conducted informally by summarizing key points at the end of each interview and asking participants to confirm or clarify the researcher’s understanding. In addition, an audit trail—including all versions of the codebook, analytic memos, and decisions about theme development—was maintained to enhance transparency and replicability of the qualitative procedures.

The qualitative method followed the thematic analysis procedure described by Creswell (2013) and was used to analyze the data collected from semi-structured interviews aiming at obtaining good findings concerning students’ speaking performance after undertaking intervention measures. The analysis process has been done systematically to come up with key themes, patterns, and concepts within transcribed data (Strauss, 1990). Codes are assigned to segments of text that represent specific ideas or topics related to the research questions. Coding of qualitative data involves assigning labels or codes systematically on segments of texts so as to identify patterns, concepts, or themes in the data that have been extracted from literature sources available during research planning phase. In the current study, the qualitative data were transcribed and coded into different themes, including the impact on English-speaking performance associated with PP intervention for ELT students; contributing factors toward creating a language learning environment, overcoming issues enhancing speaking performance, and motivation and engagement shifts.

3.5 The intervention

In the conducted study, both CC and EC underwent a parallel treatment regimen. As stated in Section 3.1, the quasi-experiment lasted 12 weeks. Table 2 presents the procedure of the intervention for both classes in this study.

Table 2

Table 2. The intervention in experimental class (EC) and control class (CC).

Similarities between pre-speaking tests held on week 1 and post-speaking tests administered on week 12 were evident from four items included in Table 2. The VSTEP rating scales used assess English-speaking proficiency with respect to grammar, vocabulary, pronunciation, fluency, and discourse management (Nguyen et al., 2020). The same book New Cutting Edge by Longman ELT in 2013 was used among EC and CC students as the pre-intermediate level textbook so that teaching materials remained consistent regardless of groups with various topics in it such as leisure and lifestyle, important firsts, at rest–at work, special occasions, appearances, time off, ambitions and dreams, countries and cultures, old and new. Each group conducted a 45-min lesson on speaking skills once per week.

However, the CC applied a traditional approach to teaching language through Presentation–Practice–Production (PPP), while the EC underwent a PP-enhanced intervention. It also included elements that are compatible with PERMA model. The detailed lesson plan provided in Appendix 1 illustrates the implementation of the PP strategies including introduction, vocabulary building, group discussion, individual presentations, and reflection & homework.

It should be noted that there were no interviews conducted among control students during week 12 compared to selected experimental students who participated in semi-structured interviews.

4 Findings and discussions

4.1 The influences of the positive psychology intervention on students’ English-speaking performance

4.1.1 Comparing pre- and post-speaking test results between the CC and the EC

The outcomes of the independent-samples t-tests conducted to compare the pre-test and post-test scores between the CC and the EC are shown in Table 3.

Table 3

Table 3. Comparison the pre-test and post-test scores between the CC and the EC groups.

Levene’s test statistics employed at the beginning of student language improvement studies subtly suggested a balance. However, by post-test revelation, F statistics signaled significant changes (p = 0.003). This shift was confirmed by t-test that showed a convincing t-value of −4.889 (p = 0.000), and unequal variances were also indicated by Welch’s test. The 95% confident intervals that had been ambiguous before became clearer, indicating significance starting from −1.23468 to −0.51589 or −1.22084 to −0.52974. In conclusion, this has shown no significant variation in pre-test scores between CC and EC; however, there was marked difference for post-tests scores among them suggesting that there is something special about the PP intervention on EC students’ English-speaking performance.

4.1.2 Comparing pre- and post-speaking test results within CC

The paired samples t-tests conducted within the CC for both pre-test and post-test scores are presented in Table 4.

Table 4

Table 4. Comparison the pre- and post-test scores within the CC, including specific evaluating criteria.

Table 4 indicates that grammar, vocabulary, pronunciation, fluency, discourse management and total average score were not significantly changed by the paired differences and associated t-tests, respectively. Notably, there is a little but non-significant change, according to the discourse management t-test. With a p-value of 0.095, discourse management was much more important than the typically accepted 0.05 threshold. The lack of a statistically significant difference suggests that the change in discourse management scores is more likely the result of chance than a genuine intervention impact. Additionally, the CC did not experience any statistically significant changes in test scores during the pre- and post-test periods. High-to-very-high correlations between pre- and post-test results demonstrated that the criteria were consistent with one another. If the students’ speaking skills did not significantly improve throughout the intervention time, it may be because the CC’s typical teaching technique did not work.

4.1.3 Comparing pre- and post-speaking test results within EC

The paired samples t-test was calculated in Table 5 to assess the within-group differences in speaking test criteria for the EC between the pre-test and post-test phases.

Table 5

Table 5. Comparison the pre- and post-test scores within the EC, including specific evaluating criteria.

The statistics indicate that grammar scores improved a little but not significantly with t = 0.083 and p-value = 0.162, respectively. The speaking performance of experimental participants improved significantly which was evident from pre-tests to post-tests (t = 1.500, p = 0.000). Besides, pronunciation did not show any notable difference though (t = 0.16, p = 0.162). There was a meaningful change in fluency as demonstrated by this statistical measure (t = 0.792, p = 0.001). Also, considerable discourse management increased dramatically (t = 1.250, p = 000). The average rating for overall EC speaking competence rose statistically (t = 0.7583, p = 000). Noticeably, these results clearly suggest that the PP method had profound effects on the development of the participants’ speaking skills.

The numerical findings presented in this study complemented other extensive research concerning the use of PP strategies in teaching languages. This study supported previous findings that using PP assistance resulted into better speakers among learners. Sauro and Sundmark (2016) disclosed how health and happiness improved, while life skills were added to the academic curriculum for Swedish students. Conventional language improvements led to increased well-being in Western US Sauro and Sundmark (2016) but it was not statistically significant.

This research distinctly explains how different speaking skills are affected by the PP intervention at EC. This comprehensive review is comparable to Abdolrezapour and Ghanbari’s (2021) study of listening comprehension. The previous research emphasized specific skill development that had remarkable effects following the PP intervention. Among EC participants, importance was given to grammar, fluency and conversation management. This shows several linguistic skills can be developed through PP.

4.2 Benefits and challenges of implementing PP intervention in speaking classes

The qualitative data gleaned from semi-structured interviews conducted with the students in the EC shed light on the aspects of implementing PP strategies in a speaking class.

4.2.1 The impacts of PP intervention

The study participants reported a positive impact on their speaking skills with observable changes in vocabulary, fluency, and discourse management among others.

The PP approach made a significant contribution to students’ vocabulary in spoken performance. One of the main strategies was the use of different and interesting subjects connected with the course syllabus. Every week, the students engaged into theme-based discussions about leisure time and lifestyle, aim, and dreams. Such an implementation not merely enhanced learning but also brought students across a rich variety of—associated with particular contexts—lexis. Students who scored highly, though, reported some progress in their acquisition of words. In relation to this group, those who tried to employ PP techniques saw that their lexical range had expanded. Student 9 pointed out “…every week we were talking about something new and it has been helping me learn more words I’ve never used before;” …. I met many new words which I have not used before; discussing them in class only helped me remember them again….” Also, these PP activities had challenging communicative exercises that could be done together so as to interactively enhance vocabulary usage by students. This practical application ensured better comprehension and retention of vocabulary items. “I remember at work when we had to speak on some issues then those words became part of my talk,” stated Student 12.

Concerning fluency, the environment supported by PP contributed to improvement in students’ speech rate which was reflected through long speeches without hesitations. Sharing experience with classmates caused the fear of silence disappear for this student: “I talked longer because it was required by tasks; thanks to friends and teacher help I felt sure enough and did not stop often…” Students talked more freely during group discussions, role-plays or when speaking impromptu. PP activities also included time limits for speaking to challenge learners into expressing themselves within set timescales as well as contributing more toward improving pace and rhythm in speech. “The timed exercises made me aware how quickly I would go; henceforth helped my flow such arrange while talking…” (Student 24).

As for discourse management, one fundamental aspect was that during speaking tasks thematic development constituted a locus of attention. Engaging in discussions and presentations on different subjects allowed the students to learn how to think coherently. In an interview by Student 9, he said, “. Thus, each topic had its structure and all I had to do was order our ideas around it after reading through…” Furthermore, reflecting on the speaking tasks helped them receive feedback concerning their discourse management. By doing so they are able to look at what they need to improve upon when trying to arrange their thoughts in following activities. According to Student 6, “…it was like talking about how I did on each task afterwards really helped me with my speaking. It taught me how better I could manage my talks….”

This concern on conversations based on themes is consistent with CLT approaches (Celce-Murcia, 2001), which underlines the significance of contextualized enriching topics for vocabulary learning. Second, this combination of interactive and cooperative exercises coincides with sociocultural theory as argued by Vygotsky (1978) who identified social interaction as an important approach in second language acquisition. The increase in fluency due to communicative extended speech and timed exercises is also consistent with research supporting CLT (Celce-Murcia, 2001) that stresses meaningfulness of language use in skill development. Moreover, focus on thematic development in discourse management corresponds with content-based language teaching as suggested by some studies (Lyster, 2011) which recommend teaching languages using content.

4.2.2 Contributions to language learning environment

The provision of a supportive environment ensured that the language learning atmosphere was rich for its students. The PP intervention was centered around to encourage students to show their ideas. Student 18 added, “…the positive environment made me feel comfortable sharing my thoughts because I knew there were people behind me”.

The feeling of being supported and encouraged created a perfect environment for the students to take linguistic risks hence fostering a more engaging and participatory learning atmosphere. The emergence of diverse topics in line with PP strategies enhanced the learning environment. The sentiment was expressed by student 24, “… I learnt about cultures other than my own while talking about different things in their languages. It helped me obtain a different perception…” Although not all details are available, the language component of the classroom could be seen as quite comprehensive due to the variety of important materials.

The data analyzed revealed that the significance of a friendly classroom environment in language learning is consistent with the welcoming and supportive language learning atmosphere by PPs (Dörnyei, 2005). Moreover, there were very many subjects involved which made it quite holistic process of language acquisition, and this is consistent with research on integrating culture into language programs (Kramsch, 1993; Oxford and Cuellar, 2014).

4.2.3 Motivation and engagement changes

The infusion of PP intervention into language education had a discernible impact on students’ motivation and engagement levels. As such, Student 6 witnessed his speaking skills taking off added that “…I felt more eager to participate in class activities” simply because these students were encouraged, thus leading to positive attitude toward English-speaking lessons. Similarly, Student 9 said. “PP added lots of stuff like tasks that made things interesting…” since he wanted something different from what he usually goes through daily.

The effect on motivation, however, did not affect all students in the same way. For one student, it was observed that “…few people’s keenness jumped but it is not a cure for everybody; there were still challenging days….”

Student 9 also shared about involvement saying “… like I was engaged in group talks more. I got more interested in what we were learning in class by some assignments that required us to work as a team…” This insight points out the cooperative and interactive nature of PP strategies which contribute to increased student engagement.

The finding indicates that positive impact on motivation and engagement aligns with research conducted by Nguyen (2023), which highlights motivational advantages of using PP strategies in language education. In addition, this finding corresponds with several studies underlining the importance of motivation in language teaching and learning (Dörnyei, 2005). Varied and interesting activities introduced through PP strategies are similar to other studies advocating learner involvements via different teaching methods (Abdolrezapour and Ghanbari, 2021; Bodner, 2016; Wu, 2023).

4.2.4 Challenges in enhancing speaking skills

Despite the merits, the use of PP interventions in developing speaking skills might seem to present several certain difficulties. One big obstacle expressed by Student 16 was early adaptation to a new mode of teaching, “…it took me a little while to adjust myself into the new style of learning since PP differed from how we used to do things….” Furthermore, the participants had problems with investing time into self-reflection required by PP. As Student 24 complained, “…some activities made us think deeply about our own lives, which could be awkward for some; those times were hard for me to open up….” Another challenge related to the diverse needs and preferences of students. Student 18 noted “…whereas others did not favor everyone among such fun-filled activities plus fun ones only featured every now and then….”

These difficulties in adapting to new instructional strategies and addressing the needs of a wide range of students were similar to challenges experienced while implementing innovative teaching methods (Kramsch, 1993; Larsen-Freeman and Anderson, 2011).

4.3 Overall discussion

Taken together, the quantitative and qualitative findings suggest that the PP-based intervention exerted a meaningful influence on students’ English-speaking performance, particularly in vocabulary, fluency, and discourse management. The significant gains in these dimensions for the experimental class, contrasted with the non-significant changes in the control class, indicate that the improvement is unlikely to be attributable to normal course progression alone. Instead, the data support the interpretation that PP-aligned speaking activities, embedded over 12 weeks, created conditions that facilitated more confident and extended oral production.

These results can be interpreted through the lens of positive psychology and established learning theories. From Fredrickson’s (2009) broaden-and-build theory, the frequent elicitation of positive emotions (e.g., enjoyment, pride, gratitude) during group discussions and presentations likely broadened learners’ attentional focus and cognitive flexibility, enabling them to access a wider lexical repertoire and to organize their discourse more coherently. Over time, these broadened states may have “built” enduring resources such as speaking self-efficacy and willingness to communicate, reflected in the qualitative reports of increased readiness to speak and reduced hesitation. This mechanism is consistent with previous findings on Foreign Language Enjoyment and classroom anxiety, which show that positive and negative emotions are distinct and differentially related to performance.

The findings also resonate with motivational perspectives, particularly Dörnyei (2005)‘s view of a supportive classroom climate as a key determinant of L2 learning success. Students’ accounts of a “comfortable,” “encouraging” environment and supportive peer relationships suggest that the PERMA-infused tasks contributed to higher perceived autonomy, relatedness, and task value. This aligns with the observed improvement in fluency, as learners who feel safe and valued are more willing to take risks, sustain speech, and participate actively in communicative tasks. At the same time, some students reported that the intervention did not fully overcome fluctuations in motivation or discomfort with self-disclosure, reminding us that PP is not a universal solution and must be adapted to diverse learner preferences.

From a sociocultural perspective, the emphasis on collaborative group work and thematic discussions can be seen as creating zones of proximal development in which the students co-constructed meaning and scaffolded each other’s performance. The improvement in discourse management, in particular, may reflect repeated practice in structuring ideas, sequencing arguments, and responding contingently to peers—core processes emphasized in communicative and content-based language teaching. The qualitative evidence that students became more aware of how to “organize” their speaking, and could transfer vocabulary and expressions to real-life contexts, suggests that the PP-enhanced tasks helped integrate cognitive, affective, and social dimensions of learning.

Finally, the reported challenges—such as the time needed to adjust to a new teaching style, reluctance to engage in deeper self-reflection, and variation in preferences for “fun” activities—highlight important boundary conditions for PP interventions. They indicate that successful implementation requires careful explanation of the rationale, gradual introduction of reflective elements, and flexibility in task design to accommodate different comfort levels. These nuances are important for avoiding overly optimistic claims and for situating the present findings within a realistic understanding of classroom complexity.

5 Conclusion

This study provides empirical evidence that a positive psychology intervention grounded in Seligman’s (2011) PERMA model can enhance the English-speaking performance of pre-intermediate EFL students at a Vietnamese university. Over a 12-week period, students in the experimental class, who experienced PP-aligned speaking activities, showed significant gains in vocabulary, fluency, and discourse management on a VSTEP-standardized speaking test, whereas the control class did not demonstrate comparable improvement. Qualitative findings from semi-structured interviews further revealed that learners perceived benefits in terms of increased confidence, richer vocabulary use, more coherent speaking, and a more supportive classroom environment, alongside challenges related to adapting to new teaching methods and engaging in personal reflection.

Several practical implications arise from these findings. First, at the level of classroom practice, EFL teachers can systematically incorporate PERMA-based principles into speaking lessons by designing tasks that elicit positive emotions, promote deep engagement, strengthen peer relationships, connect content to learners’ personal goals, and highlight incremental accomplishments. Examples include thematic discussions on personally meaningful topics, cooperative projects with structured peer support, brief reflection and gratitude exercises related to language learning, and transparent goal setting and feedback for each speaking task. Such practices appear particularly beneficial for learners similar to the present sample—pre-intermediate students in a Vietnamese private university—who may experience anxiety and limited opportunities for authentic oral communication.

Second, the study underscores the importance of aligning assessment instruments and interventions. The use of a VSTEP-standardized speaking test allowed us to capture changes in specific components (grammar, vocabulary, pronunciation, fluency, discourse management), while the interviews illuminated the affective and motivational processes underpinning those changes. Future programs can build on this combination by including complementary measures such as self-efficacy scales, enjoyment/anxiety questionnaires, or classroom observation, thereby offering a more comprehensive picture of how PP interventions operate.

Third, the nature of the intervention itself—12 weeks of integrated PP activities within a regular speaking syllabus—suggests that positive psychology does not need to be an “add-on” but can be woven into existing curricula. At the institutional level, this calls for professional development that familiarizes teachers with PP concepts and offers concrete examples of PERMA-aligned speaking tasks suitable for local conditions. Curriculum designers may also consider embedding PP principles across skill areas (listening, reading, writing) to promote coherence and maximize transfer.

Several limitations should be acknowledged. The sample size was relatively small and drawn from a single university and proficiency band, which restricts the generalizability of the results. The study focused on short-term outcomes over one semester; thus, it remains unclear whether the observed gains in speaking performance and affective variables would be maintained over longer periods. Furthermore, while standardized speaking tests offer objective indicators of proficiency, they may not fully capture pragmatic, intercultural, or spontaneity-related aspects of communicative competence. Future research could address these limitations by employing larger and more diverse samples, longitudinal designs, and a broader set of assessment tools. It would also be valuable to examine how PP interventions influence other language skills, different educational levels, and varied institutional contexts.

Despite these constraints, this study contributes to a growing body of evidence that positive psychology, when thoughtfully integrated into EFL instruction, can support both linguistic and psychological aspects of learning. For teachers, it offers concrete ideas for creating more engaging, supportive speaking classrooms; for institutions, it suggests a feasible framework for innovating language pedagogy in ways that attend to students’ well-being as well as their performance.

Data availability statement

The original contributions presented in the study are included in the article/Supplementary material, further inquiries can be directed to the corresponding author/s.

Ethics statement

The studies involving humans were approved by the rector of Thanh Dong University (TDU). The studies were conducted in accordance with the local legislation and institutional requirements. The participants provided their written informed consent to participate in this study.

Author contributions

VN: Writing – review & editing, Writing – original draft. KN: Writing – review & editing.

Funding

The author(s) declared that financial support was received for this work and/or its publication. The study was supported by Thanh Dong University (Hai Phong, Vietnam), which covered the article publishing charges for this article.

Conflict of interest

The author(s) declared that this work was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Generative AI statement

The author(s) declared that Generative AI was not used in the creation of this manuscript.

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Supplementary material

The Supplementary material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/feduc.2025.1698998/full#supplementary-material

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