Plus, the coolest supplies to get kids excited for back to school.

Gearing up for back to school starts with one of these great kids’ backpacks. Not only are they cute but they’re also functional for lugging lunches, water bottles and library books. But the right backpack has to do more than carry all your kid’s essentials—it also needs to be comfortable. So what should you look for to ensure a good fit?

Choose a bag that is properly proportioned to your kid. Most preschoolers don’t need a full-size backpack so look for something smaller that they can carry on their own. Most elementary school kids will need a backpack big enough to hold their lunch, water bottle, books and a folder. Your best bet is to take your kid shopping so they can try on different bags to check the size and to make sure it suits their style. (So resist the temptation to buy a bigger bag that’ll last a few years; it can cause back and neck pain.)

Other things to keep in mind: The bag should have wide padded shoulder straps for adequate support; a padded back for comfort; water-resistant material that’s durable and lightweight; and for extra safety in the winter, reflective straps that help your kid stay visible.

Now let’s start shopping!