I also have our school day set up with 1/2 hour increments in which an older child will take a break from school to watch the younger non-schooled children. This is such an amazing help to me. Before doing this my little children were constantly getting into things they are not suppose to get into while I was trying to teach my older children. I lost so much teaching time chasing my little ones around. Now I can relax and teach knowing that my little ones are being watched. This is also good for the older children in that they get to spend quality time with their younger siblings and the little ones really look forward to it.
I have to admit, when people ask about my large family, that it really is easier now than it was when I only had 2-3 children. I believe in the philosophy of The More the Merrier. It's true, the more you have the easier it gets because you have so much more help than when you only had 2 or 3 little ones by yourself. Of course you have to teach and train your children to help, it doesn't come naturally. I love watching my little guys look up to their older siblings for help and watching the older ones care so affectionately for their younger siblings, it's so precious to me. I love my large family and wouldn't have it any other way.