Richard Robinett Penn State University Assessment of student understanding in quantum mechanics informing the development of novel problems and visualization methods We discuss the development of an assessment tool for probing the evolution of student understanding of various aspects of quantum mechanics over the undergraduate and graduate career. Informed by the results, we have also developed novel problems at the advanced undergraduate level which emphasize conceptual understanding and visualization ability, using mathematics at a level consistent with standard senior level physics coursework, but which also make contact with modern research results. We describe specific problems involving (i) idealized models of quantum well structures, (ii) free particle wave packets and squeezed states, and (iii) wave packet revivals in the infinite square well.