For schoolers of different ages and grades, different children must carry different amounts of stuff in class. As children get older, this usually gets heavier due to the more difficult the class and the fact that they have to take the books home and go to school.
This means that the older they are, the heavier the stuff they need carry, and the greater the support and demand of the bags, that is important, so the effects that they must carry all the extra weight with them for most of the day will not affect them in their later life. Two school bags are indeed more supportive that can be used in school, but it is important to ensure that they carry only what they need without adding extra weight that may affect the child and his posture.
Younger children may not need the support of their school bag without a lot of things, although it is always an advantage if it can distribute the weight across the body. Having two straps makes the back, neck and shoulders of the bag safer. Besides, if the weight they carry is heavy, then a school bag with sponge padding at the back panel is necessary, which will reduce the stress over the shoulder and back.
These points will help you choose a school bag that is right for your child, both supportive and stylish. Please make sure your child tries on it before buying to make sure it fits your size and it won't be too big or too small for the child.