Upper-division physics students often struggle with quantum concepts during their first exposure to full-blown quantum mechanics. Research into student learning of quantum concepts with tools such as the Quantum Mechanics Concept Assessment have provided insight into student learning around concepts such as superposition and time evolution of states. But how does our understanding of quantum instruction gained in the continuum inform student learning in a “Spins First” approach? This talk will present an overview of research on instructional challenges involved in learning quantum mechanics along with a discussion of challenges associated with the move from discrete bases to the continuum. Evidence will also be provided that we need new assessments to better understand the challenges associated with moving between representations and/or bases.