Setsubun comes either on February 3rd or 4th depending on the year
On the night of Setsubun, many households do mame-maki - a bean-throwing ceremony. They fill a masu (a wooden measuring cup) with roasted soybeans and throw the beans all about the room, shouting "Oni wa soto! Fuku wa uchi!" meaning "Out with the goblins and in with fortune!" They also open the windows and throw the beans outside. Mame-maki began as a New Year ceremony (in the traditional Japanese calendar) to drive out evil spirits and the seeds of misfortune, as well as to pray for the family's well-being and good business.
After the mame-maki is over, everyone eats the same number of beans as their own age. It is believed that by doing so, people will be free of sickness during that year.