This is a warning in Cleveland Heights, Ohio, that kids aren't allowed - that kids are a problem - interfering with commerce or causing flash mobs or whatever.  

We saw this same treatment of youth a few years back when Terminal Tower folks put up warnings on the RTA - then banning kids was called "parental involvement".  

We have a problem.   We have a big problem.   Much of our society is "uninvited".

What's the cause?

Poverty?

Section 8 housing?

Nintendo?

Global warming?

Lead poisoning?

Skateboards?