I work 35-45 hrs/wk, and for summer, I am taking 9 credits. When Fall starts, I will be taking 14 credits. My husband works nights so it's just me and our two children.
I find the time to study once the kids go to bed. I usually am up until about 11

m, then up again at 4:30am. I study when we go anywhere by car (hubby driving, of course...lol), I study in between dinner and baths. I study whenever I can.
The first couple of semesters, I got a few grants so I got lucky. Now, I'm all in on student loans. We don't have much extra money to pay for books and such, so I'm going to be paying off my education for quite sometime. However, to me, it's worth it because I will be doing what I truly love and have worked so hard to get!
My pre-reqs have taken me 1 year to accomplish. I started off only taking one or two classes. Each semester I have bumped up the credits to see what I can handle, and so far (knock on wood), I have been successful.
Best wishes to all of you in your education.