Poster advertising the Duncan World's Championship Contests that was open to boys and girls 15 years and younger, circa 1964. The total value of prizes was $25,000 US (about $228,840.00 in 2022).
See the poster up close. The viewer lets you zoom in/out on the poster or drag the poster to move your view. Poster is courtesy of the Duncan Family Yo-yo Collection at the National Museum of American History, Archives Center.