No balls. Players are facing coach. On "down" they get into a triple threat position showing their hands (for a pass). On "catch" they clap their hands, on "shot" they jump, shoot, extend and hold the follow through.
(Variation - coach is in the paint, players space around the 3-point line facing the basket, see Shooting - Tauer form)
Progression - players walk in one direction, on "down" they jump to face coach with an inside pivot or jump stop. Work up to jogging.
(Comment - for a quick shot, catch the ball facing the basket, knees bent, and keep the ball high, don't lower it)