I went to San Diego Job Corps from 2000-2003.
I was homeless for a year prior to joining at age 18. My experience was like many others' here. Highschool dropout. No skills. A lot of drug use. Coming from an upper middle class suburb, job corps was a bit of culture shock.
I was one of maybe 10 white students in the campus of ~2000 students. Dorms were military style, white glove on the top of the locker cleanliness checks. Locked out of the dorm by 7:30 AM. My first roommates consisted of a Mexican crack dealer and a former gang member. There were gang fights and even some half hearted riots. However at exactly average height and a bit underweight no one really messed with me, not sure why. Just kept my head down and stayed out of the drama.
The first six months I studied electronics, and unfortunately it was worthless. I slept in class and mostly was there for the food. I did get my GED within the first two weeks. Everything was outdated and it was essentially just teaching us how to solder, which anyone can learn within a day. At the time, it was three years max stay for the program, and I was determined to milk it as long as I possibly could. The food was catered by Marriott, all you can eat, and I happen to love cafeteria food. 3 hots and a cot, I was in heaven.
For my second trade, I chose computer repair. I got my A+ certification after a year. There was a lot of sleeping in class there too.
For my third and final year, I finally discovered that I could attend community college while living on the dorm. The Job Corps librarian whose name I forget was amazing. AMAZING. She helped me fill out every form, got me several thousand a year in financial aid, and helped me get income waivers for every class. I maintained a three point something GPA in community college with her encouragement. I didn't finish college; my time ran out and I had to get a job, apartment and support myself, unlike many of the other more motivated job corps redditors in this thread.
What it did do however was get me off the streets, and make me into a productive member of society. I'm not earning six figures but I never dreamed I would be able to support myself, which I've done since then. I also haven't touched drugs or even alcohol since leaving the program. I've come a long way since then and am thankful for all the help provided to me.
(Throwaway because SJW redditors can be more vicious than mexican crack dealers)