class president; head class representative
The student elected to lead a homeroom class in Japanese schools, often responsible for coordinating with teachers and representing the class at meetings.
He was elected class president.
As the head class representative, you have the role of gathering the class's opinions.
Compound of 学級 (がっきゅう, 'class') + 委員長 (いいんちょう, 'committee chairperson').