Students' progression of understanding the matter concept from elementary to high school

Using the US national sample from the Third International Mathematics and Science Study (TIMSS) and the Rasch modeling method, this study identified the conceptual progression sequence of various matter concept aspects, and compared students' latent abilities against the sequence. We found that the four matter aspects, i.e. conservation, physical properties and change, chemical properties and change, and structure and composition, are interrelated. Although they differ in overall difficulty with an increased difficulty from conservation to physical properties and change to chemical properties and change and to structure and composition, the difference among them is not statistically significant at the 0.05 level. Elementary school students (3rd and 4th grades) have an average latent ability below the average difficulty of items on the conservation aspect; 7th graders' average latent ability is above the average difficulty level of the conservation and physical properties and change aspects; 8th and 12th grade students' average latent ability is above the average difficulty level of all the aspects except for structure and composition; and 12th grade science specialization students' average latent ability is above the average difficulty level of all the four aspects. We proposed a dynamic overlapping wave model of matter concept development to make sense the above-identified progression patterns.