Effect of Van Hiele's Instructional Model on Students' Academic Performance and Anxiety in Geometry among Senior Secondary Schools in Katsina State, Nigeria

This study investigated the effect of Van Hiele's instructional model on senior secondary school students' academic performance and anxiety in geometry in Kankia Zonal Education Quality Assurance, Katsina State, Nigeria. The research employed a quasi-experimental pre-test, post-test non-equivalent group design involving 180 Senior Secondary II students selected from two schools through cluster and simple random sampling techniques. The experimental group (n=98) was taught circle geometry concepts using Van Hiele's phase based instructional model, while the control group (n=82) received instruction through the conventional lecture method over six weeks. Data were collected using the Circle Geometry Performance Test (CGPT), validated by five experts with a reliability coefficient of 0.736, and the Mathematics Anxiety Questionnaire (MAQ), adapted from Richardson and Suinn's Mathematics Anxiety Rating Scale with a reliability coefficient of 0.947. Four research questions and four null hypotheses guided the study, with data analysed using mean, standard deviation, and independent samples ttest at 0.05 significance level. Findings revealed that students taught using Van Hiele's instructional model performed significantly better in geometry (tcalculated = 8.42, p < 0.05, Cohen's d = 1.26) compared to those taught using the lecture method. Additionally, students in the experimental group exhibited lower mathematics anxiety levels (t-calculated = 6.73, p < 0.05, Cohen's d = 1.01). The study concludes that Van Hiele's instructional model is an effective pedagogical approach for enhancing students' geometric understanding and reducing mathematics anxiety. Recommendations include the integration of Van Hiele's phase based instruction into mathematics teacher education programs and curriculum review to incorporate the model.