DEVELOPMENT AND APPLICATION OF A DIAGNOSTIC TEST RELATED TO CONCEPTIONS OF DIFFUSION AND OSMOSIS

In the study, it was described the process of development and application a diagnostic test identifying and documenting students’ alternative conceptions related to diffusion and osmosis. The test development procedure had three general steps: defining the content boundaries of the test, identifying students’ alternative conceptions, and instrument development. Alternative conceptions were derived from a multiplechoice test which also required free responses in addition to literature. This first draft of the test was applied to 119 ninth graders from three different high schools. The alternative conceptions gathered from this administration and literature was used for developing second tiers of the items. In this way, the final version of the test was clarified and applied to 90 ninth and 73 tenth graders at Erzurum Anatolian High School. The reliability coefficient for the whole test is 0.62, average difficulty index is 0.55, and average discrimination power is 0.41. According to the results revealed from application of the test, high school students had many alternative conceptions on diffusion and osmosis