Many states are having their school sales tax holiday this coming weekend. This can save you a lot of money if you live in or near one of these states especially when buying computers. Each state has different requirements. Check out these two sites to find out more info. You can always Google your state tax department (usually the Dept of Revenue) to find out if your state participates.
Before you go shopping make sure to go through what you already have in school supplies and clothing. There is no reason to buy more than you need even if you are saving a few dollars on taxes.
Here are several blog post from the past that deal with back to school. Check them out for more information.