This study examined the effects of cooperative and competitive learning methods on the mathematics achievement, attitudes to school, self-concept and friendship choices of Maori, Samoan and Pakeha children. Three hundred and nineteen children, aged seven to eleven, from fourteen classes in four racially-mixed urban primary schools participated in the three week intervention.After being randomly assigned to two conditions, stratifying for sex, ethnic membership and mathematics performance, the children worked cooperatively or competitively on an individualized mathematics programme. Significant gains in mathematics achievement were found for the sample as a whole. However, no overall effect for learning condition was present on any of the measures. A comparison of the scores of the different ethnic groups showed that Samoan children made the greatest improvement on word problems and scored the highest on the Cooperation, School Satisfaction, Penmanship/Neatness and Confidence subscales. On the sociometric measure, Maori children, and to a lesser extent, Samoan children in the cooperative condition made more cross-ethnic friendship choices than those in the competitive condition. The results of this study suggest the importance of further research on the use of group-oriented learning methods in the New Zealand multicultural classroom.