How might it have affected 8th grade history courses in the USA?

We might have a much better education system, like they do in Canada, for one. The war of 1812 would probably never have happened, or even the Civil War, for that matter.

Plus Ketchup would taste better and we would probably have a lot more Tim Hortons here in the US. And the Beer Store. I'm having a hard time seeing the down side.