Bandai holds a national yo-yo contest once a year to choose the Japanese yo-yo champion. It also divides tricks into 30 levels, with 10 levels each being grouped into beginner, intermediate, and advanced ranks. It also sponsors qualification trials at hundreds of department and toy stores around the country to certify what level each player is at. Each time you reach a new level, you get a stamp on a card. A full card qualifies you for a prize and means you're ready to move on to the next rank.
Bandai also holds a lot of events on Yo-Yo Day on April 4. The reason this date was chosen is because "four" in Japanese is pronounced yon; the fourth day of the fourth month can be thought of as yon-yon, which sounds a bit like yo-yo.
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