In the final year of their BEd degree in DCU, prospective primary teachers who have chosen to take mathematics as their Major Specialism are required to take a module in Subject Leadership (Mathematics). This module ran over twelve weeks (October-December) in 2017, for the third time. Funding (through DCU Teaching & Learning) was made available to promote inquiry and project-based learning. This stimulated re-conceptualising assessment for the module; the focus of the main assessment element shifted to project work where the 23 students, taking Mathematics as their Major Specialism, were required to work with their non-mathematics specialist peers. The 23 collaborated (in groups of two or three) on clearly defined projects, one being chosen by each group from a suggested list, but with the detailed specification developed by the students over several weeks. Each group was required to organize an event with volunteer participants (from the remaining 376 final year BEd students) and gather data from the event. The project, event, data, findings and recommendations that arose were all summarised and presented in poster form, initially in a seminar setting and then in an exhibition space. The team of five lecturers involved in supporting students’ project work gathered and analysed data, under the title Project in Rich Mathematical Exploration (PRiME), drawn from the posters themselves and from students’ reflections on their work. This paper outlines the main elements of PRiME, and reports on the initial findings and the direction of the team’s research.