Talk with the school's Financial Aid Counselors. There are going to be a myriad of things that they can assist you with or at least push you in the right direction. Different states have different rules and depending on the status of the school, it can make a difference in FinAid as well.
If you have a school in mind, start talking with them now, so that you can prepare. A great option is to have them go to a local Community College to the standard required classes out of the way. Some schools also allow you to test out of them upon entrance or take the CLEP to satisfy the requirement. Last thing will depend on your kids, but try to get them to take dual enrollment courses or classes that satisfy college credit.
Edit: One last thing. Go for every grant and scholarship you can. If they even slightly resemble the qualifications, get after it.