This study examines how teaching geometry and measurement in Grade 5 can contribute to the development of mathematical problem-solving competence, as emphasized in Vietnam’s 2018 General Education Curriculum. A quasi-experimental design was employed with Grade 5 students from selected primary schools, divided into experimental and control groups. The experimental group was taught through problem-based instructional situations, while the control group followed traditional methods. Data were collected using pre- and post-tests, classroom observations, and teacher reflection reports. The findings indicate that students in the experimental group achieved significantly higher results in three domains: (1) understanding and applying geometric concepts, (2) solving measurement problems with multiple strategies, and (3) transferring knowledge to real-life contexts. Teachers also reported that problem-based teaching enhanced student engagement, autonomy, and creativity. These results suggest that competency-oriented instruction in geometry and measurement not only strengthens problem-solving competence but also fosters broader skills such as reasoning and communication. The study provides practical implications for teachers, curriculum developers, and policymakers in aligning classroom practices with the goals of competency-based education.
Thuy et al. (Wed,) studied this question.