I second the clackers comment. God, they were awful. Absolutely guaranteed to remove teeth, and to scatter high velocity shrapnel after shattering. Should be #2 after Lawn Dart.

On the other hand, skis, horses and bicycles have led to far more injuries and deaths than these toys -- the main difference being that those risks ought to be clear.

BTW, making playgrounds safer did dramatically lower ED visits for significant head injuries and reduced lifelong disability rates. Sometimes blood-sucking lawyers are our friends.