We always bring water bottles with us. We bought them at Wal-Mart in the sporting goods section one year and they have an insulated over around them and a strap to carry them over your arm - then just fill them up in the water fountains. Very handy and FREE!! I wear a fanny pack and put a pack of crackers and cookies, raisins in there too for snacking. I think that you are not supposed to bring in lunch, but a couple of years ago, we did bring in a cooler (had sandwich meat, drinks) and stored it in a locker and nothing was said to us - but it was before they started searching through everything. You could probably get in bigger items in a backpack.