In Vietnam, STEM-based teaching approaches have been recommended for schools since 2018 with the integration of multiple related courses in schools. Teachers' perspectives on integrated STEM education, and how to design a STEM lesson that supports students’ learning are critical for ensuring that an integrated STEM curriculum is implemented successfully. This paper aims to describe a study applied successfully to STEM education in teaching Mathematics, in particular “Trigonometry ratio of an acute angle” in Vietnam. This study utilized mixed methods approaches with three phases: the first stage employed a quantitative study to examine the Vietnamese teachers' perspectives on STEM education. The second phase was an experiment on teaching while applying STEM education to design and organize a mathematics lesson, and the final phase was to employ a qualitative study to explore the Vietnamese students' experiences of STEM education connected with real-world problem solving and 21^st-century skills development. A total of 47 teachers and 85 students participated in this study and data was collected through multi ways of surveys and semi-structured interviews. The findings show Vietnamese teachers' perspective of the necessity and importance of applying STEM education, however, they reported facing many challenges. A lesson designed as a STEM education application and the student's feedback regards the real-world roles. Learning outcomes connect with 21^st-century skills in this study that are expected to provide the success evidence for further discussion and practice to improve the effectiveness of teaching and learning STEM education in Vietnam

Teachers’ professional development is now widely regarded as a key determinant of school effectiveness and student achievement. However, Mathematics teachers in Vietnamese secondary schools face numerous challenges in their teaching practices, such as a lack of recourse assistance, a lack of innovational teaching policy, and difficulty in using real-life examples in teaching. This study aims to identify Mathematics teachers’ professional competence components and organize a workshop to support Vietnamese teachers to enhance professional development through experiment research. A total of 40 postgraduate students on the master’s course of Mathematics Education at Saigon University are involved in this study. To reach the study objectives, we conducted three research cycles of: (1) Reviews to identify the model of Mathematics teachers’ professional competence for suitability in the Vietnamese context; (2) Developing materials and organizing the workshop on designing lessons that teach linear functional concepts in Grade 8 (13-year-old students); (3) Feedback analysis through a qualitative study with a group focus interview of 40 workshop participants. Data collection was recorded, and typed transcripts and theme development were employed in data analysis. The findings outline four criteria that serve as the cornerstone of our concept of professional competences for Mathematics teachers: I. Mathematical Knowledge; II. Interpretation of the Official Mathematics Curriculum’s Intentions; III. Understanding of Students’ Thoughts; and IV. Design of Teaching. This model was applied in materials design for the workshop and was highly appreciated and got a high level of satisfaction from participants. These findings are expected to bring benefits for stakeholders who are Mathematics teachers in schools or involved in Mathematics teacher education in higher education.

Mathematics, specifically spatial geometry, is a highly abstract discipline that requires students to use a substantial amount of imagination while studying. Geometry poses several obstacles for pupils owing to improve the instruction of spatial geometry, educators must discover, use, and integrate technology to enhance the process of learning. It is essential to enhance the process of learning. Educators find this disturbing. Augmented reality (AR) is significant in math education, providing several advantages. Examine and use the uses of augmented virtual reality technologies to construct models that assist in instructing spatial geometry. The instruction of spatial geometry. Research findings indicate that augmented virtual reality has many notable functions, including boosting engagement, visually representing complex ideas, improving problem-solving abilities, and promoting individualized learning.

In Vietnamese primary mathematics education, geometry instruction often emphasizes rote calculation and formula memorization rather than meaningful contextualization, leaving students disconnected from abstract concepts and lacking opportunities to connect learning with cultural identity. This quasi-experimental study investigates how integrating generative AI tools (ChatGPT, DALL·E, Canva) with the culturally grounded Vietnamese folktale Bánh Chưng—Bánh Giầy can support Grade 5 students’ understanding of circle geometry. Employing a mixed-methods design with 30 students divided into experimental (AI + storytelling) and control (traditional instruction) groups, the study measured cognitive and affective learning outcomes through pre/post-tests, a validated 25-item questionnaire, interviews, and classroom observations. Quantitative results revealed significant improvements in the experimental group across all measured dimensions, learning interest, attentional focus, conceptual understanding, mathematics passion, and cultural preservation awareness, with large effect sizes. Qualitative findings confirmed enhanced engagement, multimodal conceptual clarity, and cultural affective resonance. The study demonstrates that low-cost, teacher-mediated generative AI can effectively support learning in resource-constrained primary settings when anchored in local narratives. Implications for ethical AI integration and teacher professional development in Vietnamese contexts are discussed.