Your son is on his own to warm up for the 60 so he should have a good routine. For position players lower throws read higher velocity. For BP it’s ok to take a pitch or two if you can’t drive it. Also, as much as you want to get a few out it’s also good to show hitting to all fields so don’t be afraid to hit a ball where it is pitched. Don’t stand in groups gossiping while shagging balls (from experience 🤦🏾♀️). As always, have fun. It’s a great opportunity to meet some great talent from around the country in his class.