I went to post about this deal just the other day, but a ton of the lunch kits were out of stock - great news now though! It appears they are back in stock!
Currently, BabiesRUs.com is running a promotion where when you purchase a backpack at $12.99 or higher, you'll receive a lunch kit valued at up to $9.99 completely free.
To get this offer, simply add both items to your cart and the lunch kit will automatically be free.
If when you go here you don't automatically end up at the backpack selection, simply search in the search box for 'backpack' or 'lunch kit' to find the styles included in this deal.