I too use interval size to teach note reading. It is a real struggle because the public schools still use acronyms for the lines and spaces. But when a student is strugggling with a song, and I show them how they could read it with step up, skip up, same, step up, etc, and they see how much quicker it is, I usually can convince them.
Dana:
Yes, and I have found that refreshing the concept frequently is very helpful. When I ask them to WRITE the notes (say, a tricky-to-read measure) on our little lap whiteboard, sometimes they say, "Ohhh... I didn't notice that."
Printable sheet music for piano "Harp Ballad" is beautiful & full of energy! This free 2-page early intermediate piece will be a favorite for a long time.