How does the military school system work in the US? Are they allowed to recruit their own graduates into the military before the age that they recruit civilians off the streets? If your family sends you to military school, are the military able to requisition you into the army without your consent while you are still underage?
Military High schools (some go down to 7th grade) are private schools in the US. They are run in a military style of discipline and structure. There may not be any affiliation with the US military at all. Most do run a JROTC program, but it is not a requirement. Military can not sign them up before the standard age of assent nor can they be drafted with out a standard US draft. They are not getting payed to go to military school. (Other way around they are paying to go to the school.)
ROTC at the college level is different in that it is an official US military program. The ROTC members have signed a contract with government to pay for schooling return for military service.
Cadets at military affiliated schools (Citadel, VMI, VPI, Texas AM) are not required to be ROTC members and may just be going through the cadet program for some reason or other. (head to edit that a few times)
JROTC program which is the high school military program can be summed up as band practice with nicer uniforms. It has no auto military service and gets you entry into the military as an e3 instead of e1 if you want to enlist. It also makes you the second favorite target for drill sergeants.