CheerfulYank, here in the Northeast, the cutoff age for starting school is usually Dec 31, not Sept 1 like where you are!
Also, our schools never ever start before Labor Day! They usually finish towards the end of June.
In the US, even basics like school-starting age depend on where you live - there's no national standard like in the UK.
I grew up in the US and I'm learning things from this thread about other parts of the country!
On the downside, one wonders if the lack of social cohesion in the US is partly attributable to these differences. Even the inconsequential ones contribute to the cultural fragmentation of a nation. When I first moved to the UK, I was struck by its much stronger social and cultural cohesion.