Primary teachers’ views on manipulatives appear as diverse as the range of concrete resources available. Feelings ranging from, ‘I love them. I use them every day’ to, ‘I do not teach classes that require them’ or compromising with, ‘I do demonstrate with them but I do not give them out to the pupils’ were shared with the researcher. This PhD research aims to draw links between teachers’ pedagogical understanding of Teaching for Mastery (TfM) principles and the decisions they make when selecting manipulatives in their classrooms. A case study approach was adopted using qualitative data from online questionnaires (n=130) and follow-up interviews (n=14). Analysis using thematic analysis produced ten themes which this presentation will explore within the context of wider theory. Themes including teachers’ choices and preferences, continuing professional development (CPD), potential limiting factors and the role commercial schemes play will support a stimulating discussion that welcomes the views and insights of all delegates. Preliminary findings suggest that a combination of pedagogy, practicality and preference drive teachers’ choices when using certain manipulatives to teach specific concepts.