Teach the basic rules of volleyball
soft ball, open all
divide into 2 teams. Divide hall in 2 (we used benches), and put into 2 rows of 3 on each side. Back right person serves, hitting ball underhand over the divider. Other team must hit the ball back over in less than 4 hits. A point is scored if they don't hit it back. If the serving team don't hit it back over the divider then it's the other team's turn to serve. 1person can only serve for 5 points. After serving the team must rotate round (drop and add a new player if more than 6 on a team). First team to 21 wins.