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.

The concept of a continuous function at a point involves a key calculus idea, to help students learn about the content in calculus. Therefore, developing a learning environment where students can independently build concepts and related knowledge when learning this topic is crucial. Previous studies show challenges for teachers in designing lessons, however, there exist fewer number of studies discussing effective solutions to support teachers. This study fills this gap through the exploration of constructivism based visual instructions. This study employed an action research methodology involving 12 pre-service teachers at Sai Gon University, organized into three stages namely identifying issues when teaching the lesson of “a continuous function at a point”, exploring solutions, and finally discussing the best application. The findings demonstrated that using visual models in teaching helped students understand and verify hypotheses, reject wrong ones, and construct new knowledge about the continuous function at a point in an effective way. Four perspectives—numerical, graphical, linguistic, and algebraic—were used during the teaching process to solve the challenge of learning the concept of a continuous function at a point.

Este estudo investiga como um modelo visual de área (subdivisão iterativa do quadrado unitário) influencia a construção, pelos alunos, da soma de uma série geométrica infinita, e esclarece os mecanismos cognitivos envolvidos. Seguindo uma abordagem de engenharia didática, 52 alunos do 11º ano preencheram uma ficha de exercícios com quatro questões. Os dados das fichas de exercícios e das entrevistas semiestruturadas foram analisados utilizando codificação baseada no APOS. O modelo visual pareceu facilitar a conclusão (36,5% dos alunos previram corretamente o limite 1/3 antes da instrução formal) e o encapsulamento (61,5% alcançaram o nível Objeto). No entanto, a generalização para razões arbitrárias continuou sendo um desafio (apenas 34,6% alcançaram o nível Esquema). O estudo amplia a teoria APOS ao demonstrar que a totalidade visual por si só pode desencadear a conclusão e o encapsulamento, mesmo sem domínio algébrico completo. Ele também oferece um refinamento da decomposição genética para séries geométricas infinitas, destacando a necessidade de suporte adicional na generalização. É fornecido um projeto instrucional pronto para uso.

In the 11th-grade Vietnamese Mathematics Curriculum, content on parallel and perpendicular projection, and the representation of figures in space poses significant challenges for students due to the abstract nature of spatial geometry and limitations in spatial imagination. This study utilizes action research methods and GeoGebra 3D Calculator software to design AR-enhanced learning experiences aimed at addressing these difficulties. The study was conducted with 32 11th-grade students. To evaluate the effectiveness of the intervention, a historical comparison was made with the academic results of a cohort from the previous year ( n =40) who studied the same unit using traditional methods. The results demonstrate that the use of Augmented Reality (AR) effectively establishes a connection between reality and abstract knowledge. Critically, the post-test scores of the AR-assisted group (M = 8.2, SD = 1.1) were significantly higher than those of the historical control group (M = 6.5, SD = 1.5), with a large effect size (t (70) = 5.43, p < 0.001, Cohen’s d = 1.24). This significant improvement, while acknowledging the limitations of a historical comparison, strongly suggests that the AR-based learning design contributed to a deeper understanding. The study concludes that applying AR in teaching helps students understand and more effectively construct new knowledge about projections and representations in space, highlighting its potential as a powerful pedagogical tool despite challenges in implementation.

Transforming an infinite process into a mathematical object is a core cognitive challenge in calculus learning, yet many classrooms lack access to specialized dynamic visualization software. This study explores whether intentionally designed animations in Microsoft PowerPoint, a widely available tool with basic animation capabilities, can scaffold this cognitive leap within the Vietnamese context. Using an explanatory sequential mixed-methods design, 60 eleventh-grade students were assigned to either an experimental group learning with theory‑guided PowerPoint Dynamic Multiple Representations (DMRs) or a control group receiving traditional instruction over a two‑week unit on infinite geometric series. The experimental group demonstrated significantly higher conceptual gains (d = 2.25, a large effect comparable to intensive intervention studies in mathematics education) and lower cognitive load (d = 1.52). Qualitative analysis revealed that the animations triggered cognitive mechanisms of completion and totality construction, enabling students to view infinite sums as manipulable objects rather than unending processes. This study introduces a “high‑design, low‑barrier” model that promotes educational equity by enabling sophisticated mathematics instruction without specialized software. This paper offers practical design principles that teachers can implement immediately using existing classroom technology.