Assessment as a tool to Understand Students' Conceptions of the Structure of Matter

Learning progressions built and based on empirical evidence provide a foundation for advancing the state of the art of teaching. This paper contributes to the advancement of the idea that assessment can provide empirical evidence to examine the underlying theory of cognition and provides a method for developing and verifying the theory. Using a construct within the science domain of Structure of Matter as a basis for discussion, issues of how to address theoretical ambiguities and practical dilemmas are explored.