Not exactly the same circumstances, but single parent who was working near full-time over the summer I prepped (at a job I didn't get out till 3 am most nights), so it wasn't exactly a cake walk managing study time.
I think my biggest bits of advice would be: stay off the internet forums and avoid temptation to follow study schedules and advice from people who are not juggling the type of responsibilities you have. Design a study schedule that fits into YOUR life schedule (I might suggest getting up early before the kids wake ie making 4 am - 6 am designated uninterrupted study time, which will mean going to bed earlier but that will be good for the kids too anyway). Study at the park, their sporting events, whatever places they are being entertained. Do flashcards on your lunch break at work and even educate others about the stuff (I "taught" some of the people at the pizza place and the bar about physics laws, psychology phenomenas, anatomy etc...they couldn't have cared less but it was a way for me to practice recall). Listen to Khan Academy videos while you shower, and in the car. Study just before bed for about an hour. Between those things, you're looking at 2 hours a day of active study, and 1-2 of passive study, which puts you at 300 in 3 months (the recommended hours minimum). Then, make Saturdays or Sundays your designated practice test day. Book a room at the library or college campus or ANYWHERE you will be able to actually simulate test conditions. Do NOT try it while the kids are around. I did Saturdays test from 8 am - 3 pm (my dad graciously agreed in advance to babysit for 8 Sats in a row) then did Sunday relaxed review throughout the day while the kid played or we went to park or whatever (a temporary personal phone hotspot to tether internet wherever we went was very helpful for this). Then for week before test I took the week off and crammed another 2 tests while kid was at camp. I wouldn't recommend this but hey. I think I took another one overnight one time because I was in a mood (ironically my best score which was odd). Don't try to rush or cram. Map it out in advance and stick to it and get your family's agreement and support. It will absolutely suck and they will absolutely feel neglected, but they're less likely to get angry about it if you warn them about the suck in advance. I also had to eventually keep my phone off and say "no" to all extra commitments no matter how small. Your rare moments alone you will need to maintain sanity. I got dumped actually but I didn't care - people who are too selfish to respect your goals are not people you want on the wagon for this ride. You'll do great, hang in there and stay focused! Good luck.
