*65%*:**Improving Students' Understanding of Quantum Mechanics***64%*:**Investigating student understanding of basic quantum mechanics in the context of time-dependent perturbation theory***61%*:**An Investigation of Student Understanding of Basic Concepts in Special Relativity***59%*:**Exploring Student Understanding of Energy through the Quantum Mechanics Conceptual Survey***54%*:**The Influence of Student Understanding of Classical Physics When Learning Quantum Mechanics***54%*:**Improving student understanding of addition of angular momentum in quantum mechanics***53%*:**Testing the development of student conceptual and visualization understanding in quantum mechanics through the undergraduate career***52%*:**Assessing and improving student understanding of quantum mechanics***51%*:**Conceptual and Mathematical Barriers to Students Learning Quantum Mechanics***50%*:**Student understanding of basic probability concepts in an upper-division thermal physics course***49%*:**Students’ Conceptual Understanding of Quantum Physics in College Level Classroom Environments***48%*:**Student Difficulties in Understanding Probability in Quantum Mechanics***48%*:**A Repeat Performance? Challenges In Developing Robust Conceptual Understanding in Quantum Mechanics***48%*:**Improving students’ understanding of quantum measurement. I. Investigation of difficulties***48%*:**Students’ depictions of quantum mechanics: A contemporary review and some implications for research and teaching***47%*:**Improving Students' Understanding of Quantum Mechanics***47%*:**Improving Students’ Understanding of Quantum Measurement***47%*:**Improving students’ understanding of quantum measurement. II. Development of research-based learning tools***45%*:**How do students in an innovative principle-based mechanics course understand energy concepts?**