'Undo-kai': Sports Day
The opening ceremony of the 1964 Tokyo Olympics was held on October 10, which in 1966 became a national public holiday known as Health and Sports Day. (In the year 2000, the date changed to the second Monday in October.)
Many schools hold athletic events and sports meets on this day, dividing their students into color-coded teams of red and white to compete in relay races and cheering contests. Schools also hold coordinated group gymnastics and dance presentations featuring an entire class, all the male or all the female students, or even the whole student body. During the recess break, parents and relatives who have come to cheer on their children often provide boxed lunches in the schoolyard, and everyone gathers to eat and enjoy the great outdoors.
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