Unenforced by the police, but it is enforced by the schools - at least in our community. That's why all the kids I see still riding bikes to school do have helmets, but almost all of them are hanging from the handlebars ready to be worn once they get within clear sight of the school. Unfortunately the number of kids riding bikes to school dropped substantially when the law was enacted, so besides wasting taxpayer money it has also decreased fitness and increased obesity among children.