The CMP Rimfire Sporter is a pretty good venue to start kids in competition shooting. So is the NRA Light Rifle.
Check the rules, I believe both require 22s and not 17s,
The CMP GSM Master Instructor Courses also coaching the Rimfire Sporters.
When I went to the GSM MI course I was talking to several Rimfire coaches and all pretty much agreed the CZ 452 is the light rifle matches, Super accurate and easy for juniors to use.