Developing correct motion of the arm
Place a penny on the right hand and while sitting down, try moving the hand from left shoulder to right knee without the penny falling. This game will get the students to pronate their forearm and flex their wrist, without the teacher needing to draw attention to the motor skills involved. All attention is focused on the penny.
Cellists and bassists can practice this game by placing hand on left knee and moving to the right knee.