One of my very favorite things that summer was the BATMAN gum cards! I used to carry my set--and yes, I quickly amassed the whole set with tons of duplicates--in my pocket by the time Second Grade started. It was a big thick stack rubber banded together. I got quite a bit for 'em when I finally had to sell them just a few years ago.
Below you'll find a link to the art from all 55 of the cards of that first series!