My 2 younger kids go back August 31; and the oldest, just starting high school, starts August 26.
Oldest child won't actually get her supply lists till she starts school and gets lists from each teacher. I have picked up a few generic things for her, pencils, pens, paper, etc.
Younger two already have their supply lists, and they are really pretty reasonable this year. DD6 will be in first grade, and some of the things on her list are kind of annoying.
20 glue sticks, and 8 dry erase markers. Not only dry erase markers, but MUST BE Expo, and can ONLY BE black, blue, or brown. Now I have seen value packs of Expo dry erase markers on sale this year, but they are, without fail, a variety pack of black, blue, red and green. So in order to get 8 of the accepted colors, I have to buy 4 packages, and toss half of them out??
Annoying.
Anyhow, I have bought about 1/3 of the things on each of their lists. Every week when the Staples and Office Max circulars come out, we go buy the cheap sale items.
As far as clothes go, the younger two are pretty much set. Each had hand-me-downs to grow into (I only save things that are cute and clean and not too worn, so they always look nice) and I will admit to a terrible Gymboree addiction. Since my closest Gymbo is 150 miles away, eBay and I have become close friends.

Each has a nice winter coat and fall jackets. We still have to go shoe shopping.
Oldest child will need new clothes and shoes. She can still wear a lot of her shirts from spring last year, but her jeans are all pretty worn. Has anyone heard if Old Navy will have their $7 jeans sale this year? DD14 is eaasy to buy for, she is a total tomboy and t-shirts, hoodies, jeans, and tennis shoes are the extent of her wardrobe.