Abstract:
This study specifically sought to assess the content knowledge in Circle Theorems and the geometric thinking levels of in-service mathematics teachers and their students in the Senior high schools in Ghana using van Hiele’s levels. This assessment was conducted in the Tarkwa – Nsuaem and Prestea – Huni Valley Municipalities in the western region with teacher population of 104 and a student sample of 280. A survey research design was used through an adopted geometry achievement test (GAT). A 100% expected return rate was achieved since it was administered directly and was collected on the same day of administration. It was realised from the study that 89.42% of the teacher population passed with an average mean of 27.50 out of 40 marks. It was also identified that although the percentage pass was high, their van Hiele geometric thinking level was up to the level 3 out of the five levels. Again, it was also identified that the most of the student respondents had below average content knowledge in Circle Theorems with an average mean of 22.90 and a percentage pass of 48.21%. Out of the five levels of geometric thinking, the students could demonstrate their understanding of the Circle Theorems up to van Hiele level 3. The means of the test scores for the teachers and the students differed statistically significantly, and the effect size was big, according to the results of an independent-samples t-test. It was recommended that regular in-service training and workshops must be organised by educational stakeholders for mathematics teachers in Circle Theorems to help enhance teachers’ van Hiele levels of geometric thinking. Assessing students in Circle Theorems must be organised using the van Hiele levels. This will highlight their strengths and weaknesses at each level for remediation.
