The Development of a Concept Test for “Pure Matter and Mixtures” Unit

Abstract

The purpose of this study was to create a concept test with established reliability and validity to show seventh-grade students’ conceptual comprehension of the science course’s “Pure Matter and Mixtures” unit. The survey model, which is one of the quantitative research methodologies, was used to perform the research. The research group comprises 7th (n=272) and 8th (n=282) grade pupils studying in Ankara province’s Çankaya and Yenimahalle districts throughout the autumn and spring semesters of the 2021-2022 academic year. The first stage of the test questions was multiple-choice with four possibilities, and the second stage was open-ended with the rationale for the question written. Expert comments were sought to guarantee the test’s face and content validity. The hypothesis testing approach was employed to assess construct validity, and the test was found to be construct-valid. As a consequence of the analysis performed before the pilot deployment for the 35-question exam, 9 questions were deleted from the test, yielding a 26-question test. The discrimination of question 21 was discovered to be 0,27 as a result of the test’s actual implementation. The decision was made to delete this question from the tests, and the test was completed with 25 questions. The actual implementation resulted in a KR-20 reliability coefficient of 0,83, a mean item difficulty of 0,56, and a mean item discrimination of 0,49. In light of the results of the present research, a high discrimination, medium difficulty, and reliable concept exam consisting of 25 questions was developed to measure conceptual understanding as well as misconceptions.