well, i'm with the aclu on this and hope it goes up the proper channels. up in canada, we couldn't even contemplate a law like this - it's blatant age discrimination, and clearly unconstitutional. i think the relevant amendment in the united states is the 14th amendment, not the 4th. i'm really astounded that this is even in the realm of discourse, and hope the courts act to stamp it out, as they should.

that said, you'll note that the cops are concerned about kids under ten, while the neighbourhood is concerned about teenagers. politics aside, that indicates there's two different issues here. nobody's going to argue that kids under ten should be out on the streets. but it doesn't strike me as necessary to create new laws to deal with this....

a quick google search indicates that these laws have been frequently found unconstitutional over the last twenty years.
there's some hope, anyways...

http://articles.latimes.com/1997-06-10/news/mn-1927_1_san-diego