"Learning the Work of Ambitious Mathematics" project was developed to support prospective teachers learn the work of ambitious mathematics teaching. Building on the work of U.S. researchers in the "Learning in, from, and for Teaching Practice" project, we investigate new ways to make practice studyable within the university setting. Public rehearsals of Instructional Activities are used to provide opportunities for prospective teachers to explore and be scaffolded to engage interactively with complex teaching acts. This paper overviews the rationale and design of the three year project and reports on progress after one year.