<![CDATA[Critical thinking is an essential skill that needs to be developed in elementary science and social studies learning. However, preliminary observations in the fifth grade of UPT SDN 77 Rante Lemo showed that students tended to be passive, were not accustomed to providing logical reasoning, and had difficulty drawing conclusions based on observations. This study aimed to improve students’ critical thinking skills through the implementation of the guided inquiry learning model in the topic of human respiratory organs. This research employed Classroom Action Research based on the Kemmis and McTaggart model, conducted in two cycles consisting of planning, action implementation, observation, and reflection. The participants were 15 fifth-grade students. Data were collected through observation, critical thinking tests, and documentation, and were analyzed using quantitative and qualitative descriptive techniques. The results showed an improvement in students’ critical thinking skills. Students’ learning mastery increased from 26.67% in the pre-action stage to 66.67% in the first cycle and reached 100% in the second cycle. Student activity increased from 37.50% to 53.13% and 93.75%, while teacher activity increased from 55.00% to 95.00%. These findings indicate that the guided inquiry learning model, particularly when supported by simple experiments and systematic teacher guidance, can enhance students’ critical thinking skills in elementary science and social studies learning.]]>
