Spin First instructional approach to teaching quantum mechanics in sophomore level modern physics courses

As part of ongoing research in teaching and learning quantum mechanics using the Spin First approach, we are investigating student learning of basic introductory quantum concepts in sophomore level Modern Physics courses at Cal Poly Pomona in two different contexts. In one (perhaps more traditional) approach, postulates of quantum mechanics are introduced in the context of spatial wavefunctions of particles in simple potential wells; the second approach uses a Stern-Gerlach experimental context, with discrete bases of spin. Here, we compare student performances on a subset of Quantum Mechanics Concept Assessment (QMCA) posttest. We will share the results and discuss the implications for instructors of introductory quantum courses.