By Mr. David Joseph
STEMIA Junior High Science

This week in Science 8, students prepared for our Hill Climb Challenge, which will take place next Wednesday, April 16th.

Students were given a variety of measurements from different bicycles and asked to calculate gear and speed ratios for various wheel and gear sizes. We also introduced a Hill Climb Performance Index (HCPI), a new way to measure success in the race in addition to recording the fastest time. The HCPI is calculated by multiplying a rider’s mass by their chosen gear ratio, then dividing by the time it takes to climb the hill. Students have discovered that the fastest rider won’t necessarily have the highest HCPI!

On Thursday April 10, student teams headed to the schoolyard with a bicycle and selected the gear they’ll use for the race. Since the school “hill” differs from the actual race hill—which is steeper and much longer—teams had to make an educated estimate about the best gear choice. Each group has now recorded their optimum gear ratio for next week’s climb, and we’re looking forward to seeing how well their choices perform!

This challenge is designed to help students understand the real-world impact of gear selection and mechanical advantage.