If you mean in Harry Potter and the Order of the Phoenix, then it was Dolores Umbridge.
You can be a member of Hogwarts on Pottermore.com
No, education at Hogwarts ends after the seventh year.
Hermione Granger
Electrical resistance is similar to a student trying to walk through a crowded hallway in that both encounter obstacles that impede movement. Just as a student must navigate around other people, slowing their progress, electrical resistance arises from collisions between electrons and atoms in a conductor, hindering the flow of current. In both situations, the more obstacles present, the greater the resistance to movement, whether it's a student's path or the flow of electricity.
Ollivander
Northern Student Movement was created in 1961.
Northern Student Movement's population is 50.
The population of Northern Student Movement is 1,963.
Black Student Movement was created in 1967.
Student Volunteer Movement was created in 1886.
Why yes He is, based on the results of his OWLs .
Wear a pointy witch hat and long dress robes.