Enhancing achievement in mathematics involves overcomingbarriers regarding discontinuity between school and other life contexts,motivational and other affective aspects, and language factors.The utility of cross-age peer tutoring using mathematical gamesand scaffolding of mathematical discourse in overcoming these barriersis explored in a study of prepost impact for both tutors and tutees.Participants were all the seven-year-old (n = 13) and 11-year-old(n = 14) pupils in a small, rural primary school. Aftermatching and training of pairs, the project ran for five weeks,with two sessions of 30 minutes each week. Pre- and post-intervention,tutors completed the Me-As-Learner Scale (MALS), classteachers completed the Behavioural Indicators of Self-esteem (BIOS)scale with respect to both tutors and tutees, and tutors and tutees completedquestionnaires on feelings and attitudes to mathematics. Verbalinteraction in a sample of pairs was recorded pre- and post-interventionand analysed. Tutors participated in group subjective feedback discussionsat mid- and post-intervention. Class teachers gave post hoc subjectiveevaluations. Tutors gained significantly overall on MALS and BIOS. Tuteesgained significantly overall on BIOS. The tutor overall questionnairegain was not significant, but the tutee gain was. Verbal interactionsshowed marked and significant increases in use of mathematical words,strategic dialogue and praise between partners, with a correspondingdecline in procedural talk. Other qualitative improvementsin interactions were evident, and subjective feedback from tutorsand teachers was largely positive. This brief project appeared largely successfulin increasing self-esteem for both tutors and tutees, and in increasing boththe quantity and quality of interactive discussion about mathematics betweenchildren, as well as generic social and communication behavioursin the tutors. Questions remain about the longer-term duration ofthese gains, especially in different contexts. Recommendations forfuture research and practice are made.