Is there any way to water proof a book bag (back pack)?

put plastic bag on boom pack

I would go to a shoe store and buy the water proof spray and spray on the book bag let it dry for 30 minutes and respray hope this helps

There's a product called "Camp Dry", that comes in a spray can. You use it to spray backpacks, shoes and clothing to waterproof them. It will wear off eventually and can be reapplied. You can usually find it at places like Wal*Mart in the sporting goods section. It's made especially for nylon types of backpacks. Follow the directions on the can to apply it. I've used it for years. Hope this helps.

You can make it water resistant....they sell water proofing spray that can repel water. You can find it at any hardware, sporting good or large store.

i'd put my books in a plastic bag