When my kids were little (and there were only three of them!), I used to color coordinate them. I didn't just dress them in certain colors all the time. But I did make picking up their toys and hanging up and putting their clothes away easier. My oldest son had blue dresser drawers, a blue crate for his toys, and blue hangers. The next son had red and our oldest daughter had everything in pink.
Color coordinating your kids this way is also a great tool for teaching them colors, at least some of them, and teaches them to be responsible for their own things. What are some ways you organize your kids while teaching them something at the same time?