It was movie about a train that hit the a school bus full of kids and how the town had to keep going. I don't remember if all kids where killed, and I think it was a true story. Don't remember much more, just that there was a song and it was like when they were in church singing you could hear the next train.
I know this isn't much help but maybe someone remebers it.

Not sure, but maybe PopStar | Cloris Leachman | Long Journey Back, Movie Trailer. If not, when approximately was it made?

I looked into Long Journey back and it only talks about one girl, ths was a whole town learning to deal with it. I remember every time the town heard the whistle it was devastating.
It had to be in the late 80's or 90's. I want to say the song was day by day, for some reason that is sticking to my head.

The Sweet Hereafter (1997)?

I've seen The Sweet Hereafter (1997)? And that's not the one.
I do have a questions about POPSTAR- long journey back.. Does anyone know if you can purchase that movie? I have looked everywhere. There is one on Amazon that they want 54 bucks for it.

Thanks for helping.