If the army is your only choice and you have no other way of paying for college, then I suppose it might be worth looking into.
However, lots of colleges give pretty generous financial aid based on your "need," so it's not like you should necessarily expect to pay full price and be burdened with tons of loans.
Also, many state colleges (and plenty of others as well) also give fairly substantial merit aid (and some give full scholarships) to students who meet certain criteria, like having a certain SAT/ACT score, or a certain GPA, etc. I would look into colleges that offer stuff like that to see if you can qualify for some money without needing to go right to the army.
Finally, sites like Fastweb.com and others can keep you updated about scholarship opportunities for high school and college students. If you spend a little time and can bust out a really sweet essay, or have done some community service you can write about, you can usually get some good money (and a lot of scholarships usually attract VERY few students, so you would have a fighting chance).
Spending a few hours on some essay that can win you thousands of dollars seems--to me--to be a lot less time consuming than four years in the army (albeit, much more based on luck and less likely to happen). But in my opinion, joining the army should still be your last resort. They can tell you you'll never see combat, but remember that they also want you to enlist.
