AUTHOR=Herreros-Torres Diana , Sanz Maria T. , Gómez-Ferragud Carlos B. TITLE=CoRe as a tool to evaluate the pedagogical knowledge of future teachers about the fraction as an operator JOURNAL=Frontiers in Education VOLUME=Volume 10 - 2025 YEAR=2025 URL=https://www.frontiersin.org/journals/education/articles/10.3389/feduc.2025.1274102 DOI=10.3389/feduc.2025.1274102 ISSN=2504-284X