Check off electronic gadgets and accessories from your back to school shopping list when you pick up the latest goodies from Best Buy . Protect that new laptop with a stylish case, and ensure you never run out of battery life on your favorite devices with extra chargers and cables. This week, the more you buy, the more you save on back to school essentials. Purchase four or more qualifying items, and save 20%. Buy three or more, and take 15% off. Sale ends 07/30/2011.