Sixth graders at Sennett Middle School are slowly adjusting to the first week of school.
It's better, it's bigger, you learn more, said Moriah Stevens.
And, they're finding, you carry a lot more books.
I have like a whole bag, every year I mostly get more and more stuff because of projects we do in school, said Stevens.
That has parents in the district concerned.
Most of the time, I end up carrying her backpack because it's so heavy, said Jill Jackson, of Madison.
Excessive weight and improper use can cause injuries to children and teenagers. Among the symptoms -- back, neck and shoulder pain, even posture problems.
Doctors say a backpack should never weigh more than 10 to 15 percent of a child's body weight.
If a child can't pull the backpack from the ground with one arm easily, it's probably overloaded, said Jeffery Masciopinto, Neurosurgeon at Deans St. Mary's Hospital.
Choosing the right backpack is essential. Doctors say avoid single shoulder bags.
It's going to cause them to tilt to the other side -- that's going to be stressful for their lower back muscles, said Masciopinto.
And leave traditional packs on the store shelves.
It has a very large center compartment, which is going to allow children to overload it with textbooks that are heavy, said Masciopinto.
Instead, opt for a more modern backpack which have wide straps to disperse force across the shoulders, and multiple compartments to distribute the weight evenly.
Sennett is doing its part by requiring students to keep their backpacks in their lockers at all times.
The backpacks frequently were filled with all their belongings, said principal Colleen Lodholz. Some of them looked like they weighed more than the students themselves.
School officials say the policy cuts down on clutter in the classroom, prevents contraband, and most importantly, takes weight off students' shoulders.
Doctors also say parents should check their students backpacks every week or so, because younger students tend to be pack rats, carrying a lot of unnecessary weight to and from school.
Adolescents aren't the only ones at risk. Doctors say college students are more prone to back injury because they often walk long distances to class.