This paper from the National Bureau of Economic Research sounds interesting:
Cycling is popular among children, but results in thousands of injuries annually. In recent years, many states and localities have enacted bicycle helmet laws. We examine direct and indirect effects of these laws on injuries. Using hospital-level panel data and triple difference models, we find helmet laws are associated with reductions in bicycle-related head injuries among children. However, laws also are associated with decreases in non-head cycling injuries, as well as increases in head injuries from other wheeled sports. Thus, the observed reduction in bicycle-related head injuries may be due to reductions in bicycle riding induced by the laws.
Not only do I not mind children (and adults) wearing helmets when participating in extreme sports, I highly encourage it. My closest buddy in college was an extreme athlete who had become a paraplegic after a sports injury. If you're flying down a mountain or bicycling on the interstate or whatever, wear a helmet.
But this idea that children riding their tricycle around the basketball court need a helmet and pads? That I can not condone. Don't parents need to realize that injuries aren't the end of the world?
Image of sad children forced to wear helmets if they want to ride bikes via Shutterstock.