The Calculus for Kids project showed how Year 6 (aged 12 years) students could master integral calculus through the use of multi-media learning materials and specialist mathematics software. When solving real-world problems using integral calculus principles and the software to perform their calculations, they demonstrated ability commensurate with university engineering students. This transformative use of computational thinking showed age-extension, because the students were enabled to redefine the curriculum by accessing content normally taught to much older children. To verify this was not an accidental finding, further work was undertaken with a relatively smaller cohort of (n = 44) Year 9 (aged 15 years) students. The results were similar to the earlier findings with an effect size of 24 (Cohen’s d) recorded. The article explores the implications of these new findings, and the potential application to other subject areas and student age groups.