Students' Mathematical Critical Thinking Ability in Solving Open-Ended Problems

Students' mathematical critical thinking ability (MCTA) in Indonesia is still low, and one contributing factor is that students are not accustomed to solving non-routine problems, including open-ended problems. This research aimed to explore the mathematical critical thinking ability (MTCA) in solving open-ended problems using a qualitative approach with a case study method. This research involved 24 grade IX students from a junior high school in Bandung City, Jawa Barat Province, who had studied quadratic equations. Data collection included written tests for MCTA and interviews. The results reveal that students fail to meet the MCTA indicators due to their lack of practice in solving contextual problems on quadratic equations and open-ended problems. In addition, to gain a deeper understanding of critical thinking ability and the ability to solve open-ended problems, future researchers could use two separate instruments, as these abilities involve distinct cognitive processes: convergent thinking and divergent thinking.