Swirlies
Some trends should be left in the past, like the vicious swirlies given to less popular kids in schools. This is what the action of putting a kid's head in the toilet and flushing was called. This kind of bullying is less common now, as more kids choose to bully from the safety of their computer screens...
Street Playing
No matter if you were a kid in a big city or a small suburb, everyone knew the best place for playing was right in the middle of the road. If a car comes by, you better hope you can run away fast enough. This practice was a little too dangerous to keep up these days...