DEVELOPMENT OF A PROBLEM BASED LEARNING MODEL BASED ON SOCIO SCIENTIFIC ISSUES TO IMPROVE STUDENT CRITICAL THINKING SKILLS ON MATERIALS FOR ENVIRONMENTAL CHANGE AND CONSERVATIONIN SENIOR HIGH SCHOOL

This study aims to determine the validity, practicality, and effectiveness of the problembased learning model based on socioscientificissues on critical thinking skills in students.Changes in the global era in the development of knowledge and technology in the 21st century, especially related to the world of education in Indonesia. One of the explanations regarding the development of 21st century learning is critical thinking and problem solving skills, so a teacher must have innovation in learning. One of them is by developing an innovative problembasedlearning model based on socioscientificissues. This research is a development research using a 4D development research model which consists of four research stages, namely the definition stage, the design stage, the development stage, and the deployment stage. This research was conducted at Senior High School of Muhammadiyah 3 Jember, class X MIPA, academic year 2020/2021 with a total of 28 students, based on the results of the study to see the validity of getting validation results, namely 97.14% which stated very valid, to see practicality consisted of three things, first was the implementation of learning which got 82.3% results, second was the teacher response got 95.19% results, the third is the student response to get a result of 90.9%, the three things state that it is very practical, to see the effectiveness obtained from the test of critical thinking skills, the score is 81.5, which means it is very high. The conclusion from the results of the study states that the problem based learning model based on socio scientific issues is valid, effective, and practical to be used in improving students critical thinking skills.