The study used a mixed-methods, two-level cluster randomised-controlled trial design. Thirty-two classes (N = 885 students) were randomly assigned to the intervention or education-as-usual control group. Assessments of spatial thinking and creativity were completed at pre-test, post-test and 6-week follow up. Teacher interviews were conducted to understand their experiences of the intervention.

While no overall intervention-related improvements in spatial thinking were found, subgroup analyses revealed that 5th year demonstrated improved spatial thinking compared to 6th year at post-test. This may be attributable to 5th year students’ higher levels of engagement in the intervention. Unexpectedly, creativity scores were higher in the control group at post-test. Qualitative interviews identified four themes: 1) Improving spatial thinking, 2) Improving creativity, 3) Engagement, and 4) Difficulties implementing the programme.