This action research attempted to investigate the effect of integrating on students’ mathematics performance and environmental knowledge, atitudes and behaviour, and environmental education in mathematics classes. It involved two sample secondary schools and one sample primary school in under-resourced communities in Jamaica. A sample of four classes was conveniently selected. The action involved integration of environmental education in six mathematics lessons. The quantitative data were obtained by using pre- and post-tests in mathematics content and a survey on students’ environmental knowledge, atitudes, and behaviours. Qualitative data were obtained through the use of teacher interviews, classroom observations, and students’ reflections. Results indicated that integration significantly increases students’ achievement and their environmental knowledge, atitudes, and behaviours. Teaching strategies included the use of real-world problems, recycled materials, and the use of technology. Sample teachers believed that these activities engaged students and made connections with real life situations. The integration also provided opportunities to move away from traditional teaching into constructivist approaches.