I knew this song in school as well and I am trying to find it.I can add a bit more:
Late one night
Upon the great highway
I saw 3 Kings of the East
Come riding

In the sky
There shone a starry ray
To guide these kings upon
Their eager way

While noble warriors with shields and spears,
Dispelled the dangers that hovered near


If anyone knows he song this is from...I'd love to hear from you.