As my 2 1/2 year old daughter smiles at me and says "nanny nanny boo boo," I stop and ponder where that phrase originated. I mean, I said it when I was little and I'm sure my parents' generation said it and so on. It is just a special something that she picked up at daycare. It is funny what gets passed on and even if you try to keep your kids from learning this things, it is inevitable.
The same goes with riding the school bus. I rode the school bus but only from like 3rd grade on to public school. I do have an issue with my daughter riding one at 5, but only because there aren't any kids on our street and she won't know anyone, plus the fact that 10 year olds will also be riding that bus. I think kindergarten is a little young and I wouldn't have issues if she had friends in the neighborhood to ride with. Well I'll cross that bridge when I come to it in about 2 years.
For now, nanny nanny boo boo.