On the min for 20 mins (5 rounds)
min 1 - rowing x 30seconds (80-90% pace)
min 2 - deadifts @ bodyweight x 8 reps (scale to 50% of max)
min 3 - box jumps x 12 reps (60/50cm)
min 4 - rest
1 rower per 3 person's .
You can also use same barbell if its not too big job to change weights.
1 box per 3 persons.
This workout shouldnt feel like you are smashed afterwards, but if want to make it more challengin put some extra weight to deadlifts @about 60% of 1 rm and do "high" box jumps so 75/60cm.