http://www.just4kidsmagazine.com/beacon4god/july4.html This has to be one of the best sites I have found, to teach kids what the 4th is about. If you have small kids break it down, and read a little a day untill finished. Each day you will have a different subjects like; what the flag is, our pledge of allegiance, etc.
After you read each part, do a project about what you just read.
PLEASE TAKE TIME TO SEE THIS SITE!