This simulator is a fun way for students to be able to explore the concepts of net force, motion, friction, and acceleration. The simulator allows students to manipulate the different variables in 4 different scenarios. This allows them to see how the different forces act when put under different conditions. The simulator can be used in various grades, but especially in upper elementary and middle school classes. The website also has different activities and lesson plans that other teachers have written that include the simulator. This is a great resource for teachers because it gives multiple ways to use the same simulator.