An early 1930s-era Donald F. Duncan, Inc. combination contest flyer and trick sheet. Apparently, by the time this sheet was printed and handed out, there were more than 100 yo-yo tricks to learn.
The name "Yo-Yo" was a trademark registered with the U.S. Patent Office as number 300,504. Of interest, the design and sequence of illustrations in Figures 2, 3, and 4 appear identical to those found in a Flores pamphlet from around 1928-1930 (the earliest known printed yo-yo trick sheet).
Shown on the front of the flyer is a Duncan Tournament yo-yo (see also image of "Robert Nickels' Duncan Tournament yo-yo" "Robert Nickel's yo-yo"). You were encouraged to buy only genuine Duncan Egyptian Fibre strings – 3 strings for 5¢ – to use with your Duncan yo-yo. The back of the flyer identifies and illustrates 8 yo-yo tricks to learn. In later years, these 8 tricks became the basis for a boy or girl winning an 8 trick award patch such as these ones from the 1950s.