Published in July 2015, this report details the findings of the Durham University Shared Maths intervention project on pupils from 82 primary schools across four local authorities. The intervention was a cross-age peer tutoring, developed at Durham University, where older pupils (Year 5/Year 6) work with younger pupils (Year 3/Year 4) to discuss and work through maths problems using a structured approach. The intervention was delivered by teachers, with training and support from a Local Co-ordinator and participating pupils spent 20 minutes each week using the approach, for two blocks of 16 weeks over consecutive years