I work with the basics, (standard 8-8-16, Sanford Double/Triple beat, Triplet Diddle, Accent Tap) but I always try to write with a groove. For instance, we play double beat but one section will play a groove check pattern while the other sections play the exercise. So that way the kids are having some fun while they are working fundamentals. Of course, having the seniors running the line (teaching exercises, facing command, discipline) goes a long way towards keeping them engaged and not getting bored. The other thing I do is hand out additional pieces of music for my more advanced players and periodically test them. They like the extra challenge.