This is the card that my sister-in-law, Jess, made for my nephew's third birthday party this year. I thought it was so cute I just had to share it!
Here are the measurements:card back - 4 1/4" x 5 1/2"
accordion part - 12" x 5 1/4" scored at 3 1/4" for the first flat part that you will tape down to the card back and then (3) - 2" sections and the last one is 2 3/4".
So going across you score at 3 1/4", 5 1/4", 7 1/4" and 9 1/4"
She used the Right on Track roller and the retired Circus train stamp set. Right now there is the Choo Choo stamp set that is current that you can do the same thing with though!