B.R.
S.,
After a divorce, I was a single mother of 3 young children like you. I chose to live poorly on child support and financial aid. There were no online degrees at that time. I qualified for "displaced homemaker" status and took all loans and grants offered. It took 5 years but at age 30, I got my degree and teacher certification. I have a huge student loan debt, but I don't regret it one bit.
I have been a public school teacher for 18 years and love it. I am a few weeks away from getting my phd in education. My youngest child is 19 now, but I have always been a single parent going to school. Of course, I worked full time after my bachelor's, but now that there's so many excellent online schools to choose from, you could probably work full time and go to school full time, since your kids are in school.
I recommend University of Phoenix online and Walden University online, but there are so many more now to choose from. Just make sure they are properly accredited, and it would be good if you know someone with personal experience. There are some disreputable online univs out there to watch out for.
Do you have an area of interest yet?