I'm not a single mom anymore, but I've been there. It's a tough place to be! I agree if you could go to school, raise your kids, work as a CNA, and come this far....you can do just about anything! You should definitely consider going on for your RN. While you can make good money as an LPN, I think you would have much more financial security as an RN being as though you have children to support alone. I know....easier said than done, but it's do-able.
People told me (most my family told me, but I'm sure everyone else thought it) that I'd never finish college because I got pregnant before I was done. Not only did I finish, but I'm just now finishing up my 2nd bachelor's degree. I'm about to start my first RN job in a couple weeks and I'll be making literally about triple what I've gotten used to making. I worked in fast food mostly through college and then as a CNA when I decided to go back for nursing.
I can't really say how it will change my life, but I can imagine that not having to worry myself to death if something goes out on my car will be one change. I had a car repair bill one time when I was a single mom that added up to more than I had in the bank. Without my car, I couldn't get to work. Without being able to get to work, I couldn't get more money to fix my car. Not having any support from family or my child's father didn't help.
Not to mention, do you know how nice it will be not to have to answer to a housing authority or DHS worker? There's a lot of pride that comes with being self sufficient. People are quick to look at others who are in government housing or getting food stamps and say, "it must be nice." Those are people who have never been there. There's nothing nice about hoping nobody you know will see you in the grocery store or worrying that your kid will be made fun of because they get free lunch or because of where they live. I love giving my kid lunch money and not worrying that they're embarrassed about where they live, what they wear, or what I'm driving. I love it that when they talk about something they want for Christmas, even if it's not something I'm probably going to get, that it's actually a possibility!
Congrats on making it this far! Your kids will be proud of you. Don't stop now! It's going to make a big difference.