I used to bike to work in my suit in Copenhagen. Kids are driven to nursery and kindergarten on bikes like this: http://www.christianiabikes.com/

In NYC I always thought they could benefit from real, separate bike paths and not just the bike lanes created by stripes painted on the avenues.

But honestly, I am not sure the idea of biking is going to pick up in America. Biking is popular in Denmark and the Netherlands where temperatures rarely fall below 20-25 degrees in the winter and where summer temperatures above 77 degrees is something experienced 5-10 days a year. Most American cities have much warmer summers and much harder winters - even if they had bike lanes it wouldn't be comfortable to use a bike as means of transportation.