Sunscreens should be used regularly by people of all ages to prevent skin cancer, including the most dangerous form of cancer linked to sunburns: melanoma. However, a new study shows that kids are really bad about using sunscreen consistently.

Researchers studied fifth-grade children in Massachusetts in 2004 and then resurveyed the same 360 children three years later. In the first survey, more than half of the kids said they had experienced at least one sunburn, and this rate did not change three years later.

Moreover, in the later survey, kids said they were spending even more time in the sun. In the first survey, 50 percent of kids said they "often or always" used sunscreen when outside for at least six hours in the summer. Three years later, only 25 percent said they did.

That so many kids still aren't paying heed to sunscreen messages is "troublesome," the authors said. "(E)fforts should be made to intensify current sun-protection programs while devising new and creative messages for children of this age."

The study appears online in the journal Pediatrics.