Does anyone know where I can find a free sewing/quilting pattern for a backpack for teenagers?

I want to quilt/sew a full size backpack for our kids school--not the little kiddie size ones that are for younger children.Does anyone know where I can find a free sewing/quilting pattern for a backpack for teenagers?
Wild Ginger has a software program that is free called ';Wild Things'; - you tell it how big you want and it prints pattern pieces on your printer - you just tape them together. There is a backpack with a flap, as well as a zippered messenger bag, called a shoulder bag on their descriptions. I've used this program to make matchy halloween bags. I'm just a satisfied dedicated customer - no affiliation...





I did a search for ';backpack'; on craftster.org, and got like 20 pages of homemade backpacks that people have made there. I think what might be most helpful for you might be the messenger bag tutorials below, with double straps instead of one - the straps would attach at the top and bottom. It is not that hard to do and doesn't require a pattern.Does anyone know where I can find a free sewing/quilting pattern for a backpack for teenagers?
I hope this site helps: