How Will It Move?
This unit focuses on forces and motion in a variety of contexts: tug-of-war, baseball, planetary motion, chemical bonds, and others. It begins with a surprising anchoring activity in which a ball speeds up unexpectedly, and revisits this phenomenon several times throughout the unit. Students generalize from specific examples to construct principles commonly known as the core ideas of Newton’s laws of motion. The differences between force and energy are emphasized, with rules-of-thumb being generated to decide which concept is more useful in given situations, and to address crosscutting concepts of system models, and energy and matter. The unit integrates several focal scientific practices: planning and carrying out investigations; data gathering, organization, and analysis; developing and using models; and constructing explanations and engaging in argument from evidence.