<![CDATA[This study aims to develop and validate a Critical Thinking Skills Test on Temperature and Heat (CTS-THT) for junior high school students based on Ennis’s critical thinking framework. The research employs an instrument development design, beginning with a literature review, followed by a test blueprint operationalizing five aspects of critical thinking: basic clarification, basic support, inference, advanced clarification, and strategies and tactics into essay items. The CTS-THT assesses students’ ability to analyze arguments, interpret experimental data, define key physics terms, and justify decisions related to temperature and heat phenomena. Content validity is examined through expert judgment by five validators: two experts in physics education, two in educational assessment, and one in science content. The validators rate each item on five dimensions using a 0–1 scale, and content validity is quantified using Aiken’s V index. The results show that all 42 items achieve Aiken’s V coefficients of at least 0.60, indicating satisfactory content validity. Most items are valid without revision, while only a few require minor or substantive improvements. These findings indicate that the CTS-THT is a content-valid instrument for assessing junior high school students’ critical thinking skills on temperature and heat. Theoretically, this study contributes a domain-specific, Ennis-based instrument addressing gaps in existing critical thinking and physics tests. Practically, the CTS-THT provides a curriculum-aligned instrument to help science teachers assess and foster students’ critical thinking through more targeted instruction and assessment.]]>
