How to Teach the Pythagorean Theorem: An Analysis of Lesson Plans

This research was conducted among mathematics graduates who participated in a pedagogical formation certificate program. Participants were asked to prepare a lesson plan intended for use in teaching the Pythagorean theorem as part of a ninth grade mathematics course. Eighteen out of 43 participants included a proof of the Pythagorean theorem as a component of their lesson plan. These proofs were classified in three categories: visual proofs (two participants), algebraic proofs (nine participants), and proofs by using triangular similarities (seven participants). In addition, the solved examples, homework, and evaluation questions included in the lesson plans were classified according to TIMSS cognitive levels. Of the 233 questions prepared by 43 participants, 37% of the questions were at the knowledge level, 60% were at the application level, and the remaining 3% were at the reasoning level.