The Shindana's aren't weird at all. They are from a game. There are two varieties, yellow back and red back (came in perforated sheets).
Here is part of a box cover:
The board game was pretty basic. It came with puzzles and each card had a value in puzzle pieces. Answer correctly and you get some pieces. Here is the Joe Louis puzzle:
Oddly, there wasn't a Jackie Robinson puzzle.
A few years ago a set of cabinet sized cards was discovered. The art on some of the cards differs from the art on the regular cards. Perhaps a prototype or proof set?
I've not seen the Robinson in the large format.