Practicality of Learning Sets Based on Flipped Classroom to Increase Students Mathematical Critical Thinking Ability in Class XI High School

The method which can be used to develop one of the learning objectives of mathematics is mathematical critical thinking ability by involving students to be active in the learning process. A student who has the ability to think critically is the students that have a systematic way of thinking, awareness in thinking, and have the ability to distinguish a truth from mistakes. In fact, in the learning process students are still given information clearly and directly which created a passive learners. Students also do not have their own knowledge before the learning process begins so that they only expect knowledge from educators. The impact is there are difficulties for students in learning in class due to lack of training time in questions with varying degrees of difficulty. The lack of learning resources that are easy for students to understand is one of the reasons that students lack practice in doing exercises at home to improve their critical thinking skills mathematically. The purpose of this study is to produce a product in the form of a practical learning video to develop students' mathematical critical thinking skills in class XI. The development model used is Model Plomp which consists of three phases, namely the initial investigation phase, the prototype development phase, and the assessment phase. The subjects of this study were educators and students in class XI MIPA SMAN 5 Padang. Based on the results of observations during the learning process, students look active and can solve various questions with the results of work that increases every meeting. The results of interviewing educators and students received a positive response, and based on the questionnaire analysis also obtained practical categories. So that, it can be concluded that flipped classroom practical learning can be used to develop mathematical critical thinking skills of students in class XI