We get new ones at the beginning, then start January with a new one. At the beginning of the year they get to choose their new one. When the school supplies go on sale I buy new ones at 75% off for the next semester, and they are thrilled with whatever I pick out - they just love to have a new one in January. The 75% off backpacks also make nice gift bags for birthday parties, etc. Gift wrapping paper is so expensive, and the new backpack is a treat , as well as reusable gift packaging, and at 75% off the backpack is usually less than buying wrapping paper.