Vintage History Cards

I found this set of 60 cards at a yard sale. There are about 10 different backs, some just different colors but the same pattern ( for example the blue pattern in the top left also appears in red & green).

The reverse has an answer and several questions all about US History.I can't figure out any pattern to the patterns as it were, that is, all of a certain pattern have questions about the Civil war, or The Constitution-they seem to be random.

There are no copyrights or printers/publishers name on any of them, and there is no box.
As for a date the biggest clue I've found is the question about Chicago-"In what city will the next World's Fair be held?"
Chicago had a World's Fair in 1893 and 1933.

Any information about these cards would be greatly appreciated!