Setup a 15 x 15 box as in the diagram. Two players per team in the box and two on the outside, across each other in a straight line. Other teams sets up the same way. To score a goal, a ball must be played from one outside player, to one inside player, and across to the other outside player. If the other teams gets the ball, they must play to an outside player before attempting to score.

Progression - Both inside players much touch the ball as it goes through the box. 

Key here is to keep heads up and move to get passes