backpacks will eventually wear out, this is something that no one can avoid. However, you can increase its life span and avoid any mishaps when out.
Wipe Down Regularly
Wiping your bag down, inside and out, with a damp cloth on a regular basis will help minimize the build-up of dirt.
Keep Water Out
Mold can build up on backpacks if they get wet and are not dried properly before storing or using again. Silicone spray is a great way of making your backpack water resistant, however with some materials this can darken the color and not allow the material to look the same way it was when new. Lots of backpacks come with rain covers use them or make shift ones (you could use a black plastic bag and bungee cords around the outside) to reduce the possibility of your bag, and its contents, getting wet.
heavy items put a lot of stress on the materials, not to mention your kids. Never pack more than 10 pounds into a backpack, no mater what the size is. Packing sharp objects may cause damage to the bag, including pens, pencils, rulers, compass or even a sharp pencil case. Place items so that they are not likely to pierce through the material.
This can be achieved by packing these objects tightly against other objects so that there is limited movement or even packing them within softer objects like clothing.