The Air Force offers an accredited correspondence school (Community College of the Air Force) that can get you up to a BA/BS (at least!) while you're serving. I really wish I'd done that...
You can also get credit for military service when going to a civ college (I did,) and I don't suggest to anyone that they go right into college fresh out of high school. Take a year or two off, go out and work full-time, and see what life will be like. You'll be more motivated in college (even as a civvy,) and you'll get more out of it.
I've been to college twice (I didn't graduate either time, for good reason,) once during high school (I enlisted right out of HS) and I went back in my 30's (once I knew what I wanted to get out of it - but I got clobbered and haven't been able to go back.) Both times I paid my own way, or secured grants to pay for me - but I did all the work myself, which is one Hell of a motivator to do well! Getting the Board of Governors waiver also helped (brought college down to about $60/quarter,) and keeping good grades was required for that. No trouble.
And, I was consistently able to carry at least half again the load of my classmates (generally right out of HS,) while caring for my infirm mother-in-law, and trying to run a small business and write a book (to help pay for college.) Motivation - six years in AFSOC will teach you motivation you simply cannot get in the civilian world (but you can get in any branch of the military.) The reason I haven't been back to school hasn't been a lack of motivation - I'd love to go back. It's neurological complications from having gotten hit by a car (again!) four years and change ago. It takes me longer than they'd allow for me to learn anything new, so I have to learn at my own pace.
Having a DD214 can get you in the door on quite a few things - and, if you've got an idea what direction you'd like, see if you can't get started on that while you're in. You'll get experience (which you don't get in college,) which also looks good on a resume.
Homeless isn't fun (not for the four months it was happening to me...) but motivation got me back out of it. Learning to work before going to school helps that - even if you don't enlist. And, if you go to some "professional" career (particularly MD or JD,) it makes you much more tolerable as a person! One of the easiest-to-deal with attorneys I've ever known started out as a paralegal, waited tables to get her paralegal cert, and worked at a law firm all through law school. She understands the value of working, and treats the people who work for her very well.
I can usually spot an MD or DO who "worked for a living" before going into practise by how they treat their office staff, or by the morale of their staff. If they're not happy, I'll look for someone else.
"recon" (sic - reckon)(tm) "hihgly"(tm) "seceed"(tm)
"Outback AIDS - Alcohol-Induced Dizzy Spells"