Make sure your child's backpack weighs no more than five to ten percent of his or her body weight. If the backpack is heavier, it will cause your child to start bending forward in an attempt to support the weight on his or her back rather than using the straps for support on the shoulders. When packing the backpack, make sure that pointy or bulky objects are packed away from the area that will rest on your child's back. An uneven surface rubbing against your child's back could cause painful blisters. If the backpack is still too heavy, talk to your child's teacher. It might be possible to leave the heaviest books at school, and bring home only the lighter handout materials or work books.