Students in the 5/6 Immersion classes were challenged to create a marble run out of 65 cm by 45 cm cardboard. Their target was to make the longest possible course for the marble. This started off as a one-day STEM project that lasted an entire week due to the students' engagement. Students were motivated to adapt and redesign their plans. They noticed what was working on other students' marble runs and made adjustments on their own. They were frustrated, excited, focused and engaged - the full cycle of the design process!