What to do between starts

My 11 year old son threw 78 pitches last night in 4 innings. I was wondering what do you do between starts?

League rules say he must rest 3 days after 70+ pitches so do you do any type of throwing or just rest?

I need to post a video of him and get some advice. He threw 4 innings, walked 2,struckout 8 and gave up 8 runs, not all earned.

Before high school the regimen for pitchers really does not need to be religous. If he wants he can run but for now he shouldnt be experiencing any pain in his arm. Have him play some light toss after his one day off. Then go from there. I wouldnt worry too much

If he will get just the minimum 3 days rest before he pitches again, then I would have him just play catch on those 3 days. If he’ll actually get more days off before pitching again - say 5 or more - then I would have him just play catch the first 3 days, followed by a short bullpen (30-35 pitches) on the 4th day followed by catch on the remaining days up until his next start.

Some light jogging after the game he pitches in as well as the next day is also good for arm recovery.