Parent of cadets . . . your child is now in the military. The military is responsible for his/her medical care -- not you. Most people who have served in the military will tell you that the care they received while on Active Duty was, in most cases, better than they received as a civilian.
Trust me (as I wait literally 3 months to get a routine appt with my MD) that it's true. Military doctors are extremely well trained. Access to medical care is immediate, even for non-emergencies. No co-pays, insurance forms, etc. are required.
There is no reason to keep your child on your insurance and no reason to seek civilian medical care other than for an emergency. Your child knows this -- don't put him/her in an awkward situation by insisting he/she see a civilian MD or dentist for routine care.