I have two in college at Virginia state schools now, a sophomore and a senior. Both kids will graduate with no loans. This is what we did:
1) Opened 529 Prepaid Tuition accounts for each child when they were little (elementary school). We bought 2 years of tuition & fees outright for each child with tax returns, gift money and savings, The other two years we paid for monthly through their senior years in high school. This has been a lifesaver! Their tuition and mandatory fees are 100% paid for. We only have to worry about room, board and books.
2) Limited our kids' college searches to in state universities. We have some top rated schools in Virginia!
3) Saved all our tax returns while the kids were in high school to cover room, board and books.
4) I went from part time to 3/4 time at work when the first one started college and then to full time when the second one started college. The extra monthly income goes toward room, board and books.
5) Both kids applied for every scholarship they could through their universities. DS received $20,000 over the last 2 years, which really helped when the two were in college at the same time.
6) Kids both have summer jobs and sometimes a campus job (no more than 10 hours a week) to cover all their personal expenses beyond room, board, books, phone and car insurance. DS (senior) played guitar in a band and had paying gigs for some of his college years. DD (sophomore) works with rec sports at the university gym.
Some other tips that may work to reduce or eliminate the need for debt:
1) Go to a local university and live at home
2) Dual enrollment in high school (DD did this. She entered college with an associates degree - 60 credits. She's changed her major a couple of times though, so she will not be graduating early although some of her high school classmates are able to finish in 2 years.)
3) Apply to schools that are academically beneath you. These lower tier schools want to raise their profile and attract high quality, smart kids. They offer lots of scholarship money to get them to attend. (Neither of my kids chose to attend the schools that gave them lots of money unfortunately. They had worked really hard in HS to get into the best college they could. Since we had the 529 accounts, we let them chose. If we didn't have that money set aside, we'd have pushed them to attend the schools that gave them the most money.)