Planning mathematics learning sequences as a team is becoming increasingly common in Australian primary schools and is often referred to as "team planning" or "collaborative planning." The purpose of this article is to illustrate how a multi-age Year 5 and 6 primary school teaching team, authors Scott, Rai and Kristyn, grappled with these challenges through their participation in The Victorian Academy of Teaching and Leadership's 15-week Leading Mathematics Planning (LMP) professional learning course, facilitated by authors Aylie and Ann. The authors describe and discuss an approach to collaborative mathematics planning that supported them to make productive and effective use of planning time. Ultimately, the planning team found that the sequences of learning they designed had positive repercussions for their teaching and engaged students more deeply in the mathematics. Based on its success, other planning teams in the school are exploring using the protocols they developed.