The Development of Mathematical Critical Thinking Instrument Assessment

Abstract: The research aims to determine the validity and effectiveness of the learning instruments developed. So far, the main purpose of the assessment is to determine the competence of students before and after learning, making it easier for teachers to provide feedback in order to improve the learning tools used and provide information to parents about education in schools. This research is a development research. The development model used is a 4-D model which consists of four stages, namely definition, design, development and dissemination. The results of the validation of the developed learning instruments were included in the valid category with the average validity of the total lesson plan = 4.45; and student books = 4.42. Keywords: Assessment; Critical Thingking