Road trip from Minnesota to Florida?

My husband, our kids & I are going to be taking a road-trip to an area near West Palm Beach, Florida. We're departing from Saint Paul, Minnesota in the beginning of August. This trip should not be more than a week long (including the ride back to Minnesota). Any ideas on places to stop? Our kids are tweens (11-12) and teens (16-17), so any locations that appeal to those age groups would be best.