text:  pre-approved credit card applications, ATM receipts, or basically anything else that you want to get rid of. While you should keep your tax returns forever, you should shred supporting documents for your tax returns after seven years. And your donations will help provide back-to-school supplies for area kids through the 16-pack of backpack. $20 will provide a backpack and enough supplies to give a child a good start on the new school year.