The Clef Sign penny charts are very useful for teaching beginning note reading. Initially, I teach about whichever clef the student uses. Next I talk about the five lines and four spaces of the staff. We count them from bottom to top. Next we alternate climbing up and down the lines and spaces with a penny.
After all of that discussion, I talk about placement of the open strings and have students move the penny back and forth between the open D strings and A string with the penny.
Eventually we move up and down to different scales and songs on the lines and spaces with our pennies.
Penny charts for treble, alto and bass clef are available here: