Head on over to Nordstrom Rack where you can score some big savings on backpacks. There are TONS of sales going on, here are two of my faves:
Jansport Superbreak Backpack
Only $21.97 (regularly $36)
Puma Grub Combo 2.0 Backpack & Lunch Box Set
Only $14.97 (regularly $35)
Search Style # PV1752
Shipping is free on orders over $100; otherwise, shipping is $7.95.