Take excerpts from your show and make those into warm ups. Look and see if they are playing any particular rudiments, scales, arpeggios, block chords, etc. and let those be the base of your warm ups. Aside from that, I use for the battery… 8 on a hand (as well as variants like 8-8-16 for the snares, triangles for the tenors, splits for the bass line) Double Beat (A/B), 16th note timing, and a diddle grid exercise. For the front I use the good old Green scale exercises, a Block chord exercise, individual mallet rotation exercises, and I’ll typically use our ballad as a warm up as well. All said and done, it usually takes about 10 minutes for the kids to go through everything.

Also, make sure they are doing their warm ups while marking time correctly or even while tracking.