"MyScience" is a primary science education initiative in which being in a community of practice is integral to the learning process. In this initiative, stakeholder groups--primary teachers, primary students and mentors--interact around the "domain" of "investigating scientifically". This paper builds on three earlier publications and interprets the findings of the views of four secondary science teachers and five year 9 secondary science students who were first-timer participants--as mentors--in "MyScience". Perceptions of these mentors' interactions with primary students were analysed using attributes associated with both "communities of practice" and the "nature of science". Findings reveal that participation in "MyScience" changed secondary science teachers' views and practices about how to approach the teaching of science in secondary school and fostered primary-secondary links. Year 9 students positively changed their views about secondary school science and confidence in science through participation as mentors. Implications for secondary science teaching and learning through participation in primary school community of science practice settings are discussed.