Does AMTRAK CHECK ID FOR PASSEGERS?

Amtrak's ID checking is not very consistent. Of all the times I have been on their Acela, I've only been ID'd a few times, and I have seen what looked like minors traveling alone on the train get ignored by Amtrak staff. If however you are taking Amtrak or Via Rail into Canada, you will get checked regardless of age.

Although they don't routinely check all passengers, they will definitely check unaccompanied minors. They are continually on the lookout for runaways.