日直 (にっちょく/nicchoku) Day duty.
Ok, the dictionary calls this Day Duty or Daily Duties but I have taken to calling them Class Leaders. One of my teachers became so fond of my interpretation of the term that he took to calling his own class’s Nicchoku “Class Leaders” on the chalk board. It’s the Nicchoku that usually comes to fetch you at the office and the Nicchoku that say the greetings to begin and end a class. Usually, one boy and girl are chosen each day for this responsibility. This is not the same as the elected Class Representative you see in TV shows depicting junior high school life as everyone takes a turn at it throughout the month.