Local Language Explanation-Infused Learning Material (LLE) and Activity-Based Formative Assessment (AFA): Enhancing Mathematics Learning

The study employed mixed-method research, specifically a pre-experimental case study, to explore the influence of implementing local language explanation-infused learning material (LLE) and activity-based formative assessment (AFA) on mathematics learning. The t-test for dependent samples was used to analyze the influence of LLE and AFA on students' mathematics learning. Thematic analysis of the data from informal interviews, focus group discussions, and observations was used to support the findings. The participants were 38 Grade 9 students from one of the public secondary high schools in the Philippines, identified through purposive sampling and selection criteria. The findings showed that using LLE and AFA significantly improves mathematics learning along with illustrating, modeling, and problem-solving with small to medium effect sizes. The thematic analysis results show that the use of LLE is helpful for students to study independently because they find the lessons more straightforward to understand. The use of AFA helps students enjoy learning through individual and group activities, leading to the development of analytical and critical thinking. The study recommends integrating local languages into instructional materials, providing teacher training on LLE and AFA, ensuring resources of adequate sort for formative assessments, and strengthening monitoring mechanisms to enhance the implementation of these practices in the classroom.