Hi! Ok, here's my idea!
Do suicide drills (run 1/4 of the way down the room, run back home, then run 1/2 the way down, then run home, etc). Now, here's the add on. When you reach each marker: 1/4, 1/2, 3/4, and the last one, add a drill, such as jumping jacks for 1 minute or 30 seconds, whatever. switch it up.
It is pretty fun and it keep their heart rates up there.
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