What to do?

I am sitting on the horns of a delema.
Often through the last few years I've thought I should be going to school, but could never figure out "what for?".  Ever since our church friend passed away last month it has been heavy on my mind.  He was only a year older than Joel.  What if Joel died next year?  What would happen to me? to our kids? Would I be able to afford to live on his Social Security?  What happens to me when the kids are grown and I'm cut off from Social Security?  What will I do then?  What if Joel is injured and becomes unable to care for us or himself and the social security gets eaten up by the care he will require?
I'm finding that I am feeling a strong urge to go back to school and get myself an education that will help me provide for myself and my family. 
My children are getting older, I will need to go back to work at some point, what will I do? I have no real marketable skills besides my photography and sewing. I need to be able to work while my kids are at school, and photography happens during hours families aren't working, which means also hours my kids are home, that has been a hard thing for me to reconcile with. But I'm not ruling it out. Everything I know about photography I have learned on my own.  I'd like to get more education on it and have talked about taking classes.  I don't know if I want to learn commercial photography.  I'm also a little worried with how affordable SLRs are now and the trends in portrait photography that, at least what I've been doing, is not going to be a lucrative enough business for me.
I have been praying and looking online at local colleges and the programs and degrees they offer.  I have found  a couple of programs that interest me, but I am not sure if they would be right for me.
I've been looking at trends and recently popular fields, and it seems that "green jobs" are the wave of the future. Although I'm all for recycling and not being wasteful, I'm by no means a tree hugger or a believer in global warming nor do I wish to support anything that will empower our government anymore in thinking that they should try to regulate American's any more than they already do.
One job that I am sure will never go away is the job of teacher. There will always be a need for teachers.  Maybe I could teach photography in high school, hahaha. 
What do you think I would enjoy/be good at?