I am going into my second year. I have a 10, 8, 6, 3 and 1 yr old. It has been very tough but it is certainly doable. I have been taking online classes FT up until now. This semester starts my on-campus classes so it has been stressful setting up a sitter and getting that all worked out plus worrying about picking up the big kids from school, their homework, dinner, etc. I actually think it would be much easier with just the two littles. I schedule in time to study and I also volunteer on the weekend at a place that will give me time to study without children around. I think the key is to realize when in your schedule you will be able to fit in time to study when you can actually get it done and not be distracted by things. I found that once the big kids were home from school, there was no way I could study until bedtime. I would get frustrated and they needed my attention anyway.
I would focus on organization of your time and your kids time, find out what schedule fits your family best, and stick to it. First thing in the morning when they were happy playing toys or at nap time was when I would take my tests. I would also schedule time with your hubby for when he keeps them so you can focus. In my opinion, if it is set that, for example, every Tues night from 6-9 you go to the library, it is easier on everyone. Good for you for going back and good luck!