Critical thinking is essential for decision-making, and problem-solving to help students identify their perspectives on issues. Several studies were conducted to improve students' critical thinking. However, finding specific studies that discuss developing critical thinking skills through reflection remains challenging. Therefore, this research is focused on developing students’ critical thinking through students’ reflection, which requires students to have the ability to analyze, evaluate, and create text.

The research questions for this study are as follows: 1) What are the students’ perceptions of their reflective critical thinking in Basic Reading and Writing Class A? 2.) To what extent do students develop their critical thinking through reflection? The researcher used Classroom Action Research from Kemmis & McTaggart (1988).

In this study, 31 ELESP students from Basic Reading and Writing Class A participated in data collection activities. The data collections were undertaken through observations, tests, questionnaires, and interviews at the end of the cycle. Several instruments are used in Basic Reading and Writing Class A to find out students’ perceptions of their reflective critical thinking and to find out the extent to which students develop their critical thinking through reflection. According to the findings of this study, reflection increases students' critical thinking skills.

Keywords: classroom action research (CAR), critical thinking, students’ reflection, writing