There are many muscles in the appendicular skeletal muscle system that are acting on the skeletal system to move the body in space. To ask students to memorize all of the muscle actions would be an incredibly daunting and low level memorizing task. Not to mention, the amount of time that they would retain that information would be very short-lived! Therefore, instead of memorizing, I invite you to teach some easy-to-follow rules to help students reason (as opposed to recall) in order to predict muscle actions.