M.:
Have you talked with the guidance counselor at your school? You might be able to find an internship while you are going to school to get the experience you need in your chosen career path.
Get involved in your church. Find out if there is a high school student who is wanting to take care of children on the days that you need them to be watched.
The job you have that you are losing money at? Quit. If you are paying the wages you earn in child support AND gas? It's not worth it. You are NOT earning anything to help you or your family. So quit.
Talk with your social services office and find out if you qualify for any social programs we have here in the U.S. - subsidized child care, subsidized housing, subsidized educational grants, etc. to help you through this tough time and get you back on your feet. That's what they are there for.
Good luck.