A Test Development Study for Identifying and Controlling Variables Skill: A Mixed Method Research

Abstract

This study aimed to develop a test to measure 8 th graders' ability to identify and control variables from scientific process skills. In the study explanatory sequential design was used that it one of the mixed research designs. Implementation was carried out in three phases as preliminary, pilot and actual implementation. The total implementation of the test was conducted with 1006 (21 in preliminary, 437 in pilot and 548 in actual implementation) 8 th graders in Mersin. During the implementation, 54 students were interviewed about test after actual implementation. The average difficulty of the test which consisted of 24 items was calculated to be 0.50 and the KR-20 reliability coefficient was 0.86. In this context, based on item analysis results, it can be argued that the test is a viable test that can serve its purpose. While identifying variables, some problems (carelessness, not understanding the question, etc.) were encountered by the students.