Since the PBA employs aspects of the modeling cycle, students of modeling teachers earn high scores on PBAs. PBAs promote reform by requiring non-modelers to apply effective strategies of the modeling cycle in their classroom instruction. They serve also to motivate teachers to participate in modeling workshops. Their poor results motivated him to learn the Modeling Method. Measuring the acceleration of gravity, g, for 5 different masses.
Students choose the equipment and procedure to determine gravitational acceleration.
They use the information and planetary data to find the gravitational acceleration of another planet. Two carts are placed end to end. A force causes the carts to separate and move in opposite directions. The carts have different masses, resulting in each cart having a different speed. Students plot mass vs speed and derive an equation for momentum.