This research aims to evaluate the effectiveness of the use of natural science module SMP/MTs to train critical thinking skills. The research subject of students grades VIII MTs Muhammadiyah 3 Al-Furqan Banjarmasin. The experiment was conducted in the academic year 2018/2019. Data on the effectiveness of the modules include the cognitive learning, critical thinking skills, attitude, character, social attitudes, and responses of students. Data were collected through questionnaires and observations and analyzed descriptively. The results showed module IPA developed relatively effective based on 1) the cognitive learning of students has exceeded the classical completeness, 2) critical thinking skills of students categorized as good, 3) the attitude of the character of the students are diligent and cautious good average, 4 ) social attitudes of students working together and express good average, and 5) the average response has been good. Keywords: Module, critical thinking skills, effectiveness.