Kids shouldn't carry more than 10 to 15 percent of their weight over their shoulders and on their backs. Decrease their risk of injury with these tips from Dr. Hank Bernstein of Boston's Children's Hospital:

• Help your child sort through everything before packing up and see what can be left home that day. Place heaviest items in first; the closer they are to a child's back, the less strain they'll put on those muscles.
• Buy an appropriate-size backpack, one that ends just a few inches above the waist. Use a backpack that has soft, padded straps to maximize comfort.
• Look for a pack with compartments that help distribute the weight. Or, try one of the new models with wheels, that your child can pull.
• Even though it's hipper to carry a pack over just one shoulder, encourage your kids to carry theirs over both shoulders. This will better distribute the weight.
• Make sure your kids bend their knees when they first lift their packs, to avoid further strain on their back muscles.

Recommendations from a Recent Study
Shelley Goodgold, associate professor of physical therapy at Simmons College, in Boston, says collaboration among health professionals, school officials, parents, and students is important in reducing possible backpack problems. She suggests:

• School systems buying two sets of books (one for the classroom and one for the children to keep at home), purchasing books on CDs, or making greater use of classroom overheads.
• Encouraging increased locker use, with enough time between class to return to lockers.
• Schools systems buying paperback books and/or books in volumes, rather than heavy, full hardcover texts.
• Educating children about safe carrying loads, and adult monitoring of their use.