Yes, you can bring a backpack into the Shedd. However, there are a few things to keep in mind. First, all bags are subject to search upon entry. Second, backpacks and other large bags must be stored in lockers located throughout the Aquarium. Lockers are free for the first 30 minutes, and $0.50 for each additional 30 minutes thereafter. Finally, please be considerate of other guests when carrying your backpack or any other belongings throughout the Aquarium.