The Impact of Integrating Cognitive Load Theory into Mathematics Instruction: A Design-Based Study in Iraqi Middle School Classrooms

Mathematics learning among middle school students is very complicated, especially when it involves algebra, as it needs a combination of symbols, formulas, and multi-step procedures. Regarding the Iraqi educational setting, students' performance is generally very low, with many procedural mistakes, which is caused by traditional teaching methods that do not take into account the limitations of students' cognition. This research was designed to investigate the impact of mathematics teaching based on the guidelines of Cognitive Load Theory on reducing mistakes among middle school students. A design-based research approach with a one-group quasi-experiment pre-test/post-test approach was considered for the research. A total of 25 students from the second grade of the middle school, all of whom are female students from Al-Narjis Secondary School for Girls, Wasit Governorate, Iraq, participated in the research. An instructional unit on algebraic expressions and equations, based on cognitive load theory, was created and implemented over a period of four weeks. Data collection methods included a researcher-developed achievement test in mathematics, an error analysis tool, and classroom observation. Results of the quantitative data were analyzed using descriptive statistics, t-tests, effect size, and correlation. Results from this research indicate a significant statistical impact on the achievement of the participants in mathematics following the implementation of this instructional unit (p