|81 Indonesian Journal of Mathematics Education Vol. 2, No. 2, October 2019, pp: 81~88 p-ISSN: 2654-3907, e-ISSN: 2654-346X, DOI: 10.31002/ijome.v2i2.1746 e-mail: ijome@untidar.ac.id, website: jurnal.untidar.ac.id/index.php/ijome Indonesian Journal of Mathematics Education, Vol. 2, No.2, October 2019 The Effect of Index Card Match Method to The Math Critically Thinking Skill Oriented to Higher Order Thinking Skills (HOTS) Firda Halawati Universitas Islam Al Ihya Kuningan, Jalan Mayasih No 11, Cigugur, Kuningan, West Java, Indonesia email: fbayasut90@yahoo.com Received: 6 th September 2019 Revised: 27 th October 2019 Accepted: 30 th October 2019 Abstract This study aims to: (1) find out the use of the Index Card Match method in mathematics; (2) determine the students’ ability of mathematics critical thinking with Higher Order Thinking Skills (HOTS); (3) determine whether there is an influence of the use of Index Card Match method to the students’ ability of mathematics critical thinking with HOTS. This study uses the pre-experimental method with one group for the pretest-posttest design. The population in this study was all students of Senior High School in Kadugede, Kuningan, West Java, totaling 1008 students. The sampling technique used was purposive sampling. The sample of this study was taken from two classes from class VII D as a control class with 37 students and class VII E as an experimental class with 38 students. The test instruments used were multiple-choice questions. Tests were given at the initial test (pretest) and final test (posttest). The testing data were analyzed using the independent samples t-test which has previously been tested for normality and homogeneity. The results of this study indicate: (1) the use of the Index Card Match method in mathematics learning in the experimental class was positively well and students looked serious and enthusiastic in following the teaching and learning process; (2) The students’ ability of mathematics critical thinking by using the Index Card Match method increased both in the experimental and control classes; (3) There was an influence of the use of the Index Card Match method in students' ability of mathematics critical thinking oriented to HOTS. Keywords: critical thinking ability, HOTS, Index Card Match INTRODUCTION Education has an important role in improving the process of increasing the ability and competitiveness of a nation in the eyes of the world and in improving the quality of human resources to be able to compete in the face of the times. RI Law Number 20 of 2013 concerning the National Education System Article 37 states that mathematics is a compulsory subject for students at primary and secondary education. Therefore, the mathematics learning process needs to be planned and implemented as well as possible. Mathematics subjects need to be given to all students starting from elementary school, to equip students with the ability to think logically, analytically, systematically, critically, innovative and creative, and the ability to work together. To achieve these goals, in mathematics learning it is very important to develop various aspects of skills, one of which is higher order thinking skills.