Choosing the Right School Bag
Ideally the backpack must have two straps that are thick and evenly spaced. Thin straps can dig into the muscles around the shoulders, resulting in reduced blood flow and thus adversely affecting the nerves.

The backpack can have a waist-clip/hip belt, which can help in reducing the space between the child's back and the bag. Increased distance between the two can make the bag sway more; causing the child to lose balance while walking.