JROTC is the Junior Reserve Officer Training Corps. It's the "mini" version of the collegiate ROTC, which is the same thing minus the "J."

Every branch has one. I was Army.
The goal isn't to groom a soldier out of a student, but to teach discipline, respect, and other skills (some of which are, granted, arguably military). The official mission statement is "To motivate young people to be better citizens."
lol Honestly? I signed up because it was between art, music, or that. I suck at art, and I didn't want to be in the band (which was one in the same), and I read something about marksmanship training in the pamphlet, so...lol there I was.

Stayed because I liked it. Never went on to full ROTC though.