The Compadre Portal website will be unavailable Friday evening through Saturday afternoon as electrical work occurs in the American Center of Physics server room. Down time will begin at 6PM Eastern Time on Friday. Service is expected to resume by 6PM on Saturday, July 30.

*68%*:**Categorization of Mechanics Problems by Students in Large Introductory Physics Courses: A Comparison with the Chi, Feltovich, and Glaser Study***47%*:**Student Difficulties with Quantum Mechanics Formalism***47%*:**Conceptual and Mathematical Barriers to Students Learning Quantum Mechanics***45%*:**Assessing and improving student understanding of quantum mechanics***45%*:**Changes in studentsâ€™ problem-solving strategies in a course that includes context-rich, multifaceted problems***44%*:**Assessing Expertise in Quantum Mechanics using Categorization Task***42%*:**Dynamics of Student Modeling: A Theory, Algorithms, and Application to Quantum Mechanics***42%*:**Improving Students' Understanding of Quantum Mechanics***41%*:**The Influence of Student Understanding of Classical Physics When Learning Quantum Mechanics***41%*:**Student Difficulties in Understanding Probability in Quantum Mechanics***41%*:**On the Study of Student Use of Meta-Resources in Learning Quantum Mechanics***41%*:**Improving Students' Understanding of Quantum Mechanics***41%*:**Student understanding of quantum mechanics at the beginning of graduate instruction***41%*:**Improving student understanding of addition of angular momentum in quantum mechanics***40%*:**Exploring Student Understanding of Energy through the Quantum Mechanics Conceptual Survey***40%*:**Student Views of Similarity between Math and Physics Problems***40%*:**Improving students' understanding of quantum mechanics by using peer instruction tools***40%*:**Categorization of problems to assess and improve proficiency as teachers and learners***40%*:**Surveying students' understanding of quantum mechanics in one spatial dimension**