Yes, it's possible to do the old fashioned pull-yourself-up-by-the-bootstraps and work your way through college on your own thing -- assuming, of course, that the individual involved has a healthy body and no one else depending upon him financially. However, the person involved must make all the right choices and work extremely hard. Also, some luck (i.e., living close to a college that offers the right program, living in a part of the country where college is less expensive) is often involved.
Some ways people can make this happen:
1. Choose a less expensive college. Maybe a community college, maybe a state school, but the point is that IF money is an issue, you have to choose from what you can actually afford. For most of us, the sky is not the limit, and it's important to recognize that and live with it rather than wish for what we can't have.
2. Choose the right major. This is important in a couple ways: If you change majors mid-way through your studies, it could easily add a semester or a year to your education, and that's a great deal of money. Also, some majors have more scholarship opportunities available to them: teachers and nurses, for example, can fairly easily get a scholarship/loan which is repaid through service (at full pay, of course) instead of with a check. On the negative side, these two majors do require student teaching / student nursing, which are expensive because the student must dress appropriately, have transportation and meals during the "work day", but there's no paycheck. Some majors offer co-ops (i.e., engineering and computer sc) that give the student a chance to work one semester (for pay) in a professional capacity, then study a semester; this does prolong the college years, but it makes the resume look great.
3. Choose to live at home during college. Of course, this isn't an option for everyone because everyone doesn't live within striking distance of a college. I wouldn't consider it "financial aid" to continue to live with parents who have been supporting you for years and who are willing/able to continue giving you a room in which to sleep -- assuming, of course, that you're going to school. If you're just loafing around, then it's mouching.
4. Search for jobs that'll provide the most help with college. For example, the best thing I did financially during college was to get a job as a Resident Advisor in the dorms. It didn't pay money (but then, I also didn't pay taxes on it), but it gave me a free place to live and -- except for the first and last two weeks of the school year -- the work was only a couple hours per week. This job also paid HALF my tuition, greatly reducing my bills. Colleges hire people for all sorts of jobs, and these jobs often come with big price cuts. Could you work as a secretary? a maintenance worker? cafeteria staff? Other options that could work for the right person: Work as a live-in nanny for free room and board, military service . . . even food service at least gets you free meals on occasion. Similarly, my high school daughter is in a program at school that'll allow her to earn a CNA (Certified Nursing Assitant) license before she completes her high school diploma; she'll be able to work as a low-level nurse during her college years (while working towards a BS-RN degree), which will pay more than a job at the mall AND will give her valuable experience. Typically you have to SEARCH for these jobs; they aren't as "visible" as wait-staff work or salesclerk at the mall jobs.
5. Work hard. Really hard -- as in sweaty jobs. Most teens tend to gravitate towards jobs that, honestly, are pretty easy: Retail at the mall, etc. Those jobs don't pay well because, well, they don't have to. Anyone can do those jobs. Instead look for manual labor jobs. When I was in college I knew more than a few people who loaded trucks at night for UPS. It was HARD WORK, but those people made a great deal of money. I also knew a number of people who worked on the assembly lines at IBM putting together computer components. I worked as an all-night security guard for a while. It was miserable, lonely work, and I went to class exhausted the next day -- but I did all my studying in the middle of the night, and it was what I needed to do at the time. I also worked in a factory for a while -- that was also miserable work and I hated every second of it, BUT it paid about twice what I could've earned at a fun sales job, and I needed that money.
6. Choose cheap living arrangements. Yes, four girls CAN share a two-bedroom apartment. Yes, you CAN do without a car if you live on campus. Eating out is a luxury. Spring break trips are a luxury. The problem, of course, is that most families are not raising their children to understand the difference between needs and wants, so once they're out on their own, they have trouble doing without things . . . and the result is often debt. Along the same lines, look for other ways to live cheaply: Share textbooks, print at the library, eat Ramen Noodles instead of pizza, avoid using shopping as a hobby because it inevitably leads to spending. This also means accepting that you can't always do the "fun stuff" that's available: You won't be able to take advantage of the study abroad semester, even if it IS a great opportunity.
7. Avoid debt. A college student who's working hard and is making all the right choices CAN make it, BUT if he ever gets into debt, it's going to become overwhelming. Paying off yesterday's expenditures -- whether they were necessities or luxuries -- is going to tip the scales to the "can't do it" side.
8. Realize that for most people who are "doing it on their own", there isn't going to be ONE BIG SOURCE of income . . . rather, it's going to be a patchwork of resources, and those resources will change year to year.