The Use of Bar Model Approach in Teaching Mathematics

Abstract

This study examined changes in Grade 7 students’ mathematical performance, visualization skills, and problem-solving skills following instruction using the Bar Model Approach. A quantitative pre-experimental single-group pretest–posttest design was employed with 25 purposively selected students at Cagdianao National High School, Dinagat Islands, Philippines, during School Year 2025–2026. The intervention lasted one week, with one hour of instruction per day, and addressed contextualized word problems involving algebraic expressions and formulas. A researcher-developed 20-item test and a five-level skills rubric were used. The source reports expert validation, pilot testing, and a KR-20 coefficient of .75 for the achievement test. The reported achievement mean increased from 12.8 to 16.6, visualization scores from 20.0 to 65.4, and problem-solving scores from 31.6 to 80.1. Paired-samples tests were reported as significant at p < .001; however, the achievement-test t statistic is inconsistent with the reported standard deviations and requires verification. Item analysis identified comparison problems as a persistent area of difficulty, particularly Question 16, whose correct-response proportion increased from .16 to .32. The findings provide preliminary evidence of improved assessed performance after bar-model instruction, while the absence of a comparison group and use of the same test prevent causal attribution. The study recommends guided work on comparison relationships, explicit links between diagrams and equations, and more rigorous follow-up evaluation. Keywords: Bar Model Approach, Mathematics Education, Visualization Skills, Problem-Solving Skills, Algebraic Word Problems