We interview students, a teacher and a leadership staff member at a Queensland school consistently successful in an international team modelling challenge. The study highlighted the role played by team composition, team cohesion, prioritised planning, and thorough execution. The school supported a mathematical modelling culture at secondary level by building on the open-ended nature of teaching developed in the junior school, by prioritising time in the mathematics curriculum for open-ended problems, by supporting out-of-school and cross-curricular opportunities, and by supporting student teams during intense mathematical modelling periods where dedicated time was needed.