This research was conducted to improve the teaching-learning process in the classroom, in the form of improvements to teaching materials used by teachers so far, with the hope that students will be able to think critically in addressing a problem. Improvements were made using the Tessmer development method with the aim of seeing the effectiveness of the handout teaching materials used to solve learning problems. The results showed that the handout teaching material developed proved to be effective based on aspects of classical completeness cognitive learning outcomes with a student achievement rate of 79.16%, critical thinking skills of students at 50%, and student response at 85.69%.