Head Boy or Girl

] A Head Boy or Head Girl is a seventh year student who has authority over Prefects at Hogwarts School of Witchcraft and Wizardry. Each year, both a Head Boy and a Head Girl are selected by the current Headmaster of Hogwarts. The pair of students are instructed to do duties to assist the school. They lead both the prefects and (in many cases) the entire student body.

Appointment
Before the starts of each school year, the Headmaster appoints one Head Boy and one Head Girl from all of the seventh year students. These students are chosen because of their academic achievement, outstanding reputation as a student, and an honest, good, and hard-working personality.

Prefects may have a greater chance of being appointed to this position, as both have similar expectations on the student, however this is not a prerequisite. If a prefect is elected, they may not be replaced and would then serve in both capacities.

Duties
One of the duties known of the Head Boy and Head Girl is to instruct the Prefects of their duties on the Hogwarts Express in the Prefects' carriage. On the train, the Head Boy and Girl can be seen telling the prefects when they will need to patrol the train.

Head Boys and Girls also have special responsibilities whenever required. In 1993, when Sirius Black had broken into Hogwarts, Dumbledore asked the Head Boy and Head Girl to watch over the students in the Great Hall while he and the rest of the staff searched for Black in the castle.

Other duties of the Head Boy and Head Girl are unknown.

Recognition
The trophy room contains a list of Head Boys and Head Girls. The Head Boy and Head Girl are in charge of the Prefects and should be an example to the other students. Head Boys and Girls also have the special privilege of being able to use the Prefects' bathroom in the case that they are not Prefects. The Head Boy and Head Girl, also have their only common room and dormitory.