Hockey Drill Demonstration
Split the players into 8 teams, play 4 games in the 25's. Ten minute games.
Have all the teams at the far side of the pitch playing in bibs, then once a game is completed have all bib teams moving one place either way so every team plays someone new. (this should speed up the time between games as no teams should have to swap bibs between matches)
Have a coach assigned to each team, either to play or manage that team. Once coach oversee with the timings and to record scores to see which team wins overall.
If the keepers want to play in goal they can, if not keep them outfield.