Recent reform efforts have been adopted in the United States to reimagine student learning in science. Historical reform efforts have required teacher buy-in necessary for substantive change to occur. Using a mixed-method methodology, chemistry teacher progress in implementing the "Next Generation Science Standards" in Illinois and views about the purpose of science teaching and learning were explored in the context of teachers' curriculum design decisions. The results of this exploratory study suggest that standards alone are not sufficient for implementation. Chemistry teaching and learning appear to be partially mediated by a canon of knowledge that does not fully complement the standards teachers are asked to implement.