To address the fact that students face real difficulties not knowing how to deal with unfamiliar ideas and mental models, I developed the “Decoding the Disciplines” approach along with David Pace. I specialize in leading faculty groups to make disciplinary thinking more available to students. Decoding the Disciplines can uncover the mental moves that are so automatic to an expert that they are invisible and, therefore, may not be explicitly taught to students. With Leah Shopkow I published Overcoming Student Learning Bottlenecks: Decode the Critical Thinking of your Discipline (2017). The History Learning Project (Diaz, Middendorf, Pace, and Shopkow) won the top research awards in the fields of research in teaching and learning (2009 McGraw-Hill–Magna Publications Award) and in educational development (2008 Menges Award). Outside of work, Joan likes to kayak, garden, and play games with her grandchildren.