The headmaster of the high school at Maalia in Binjharpur block allegedly beat up the student when he failed to answer a question.
The student suffered injuries and was admitted to a local health facility. Later, he was shifted to the district hospital after his condition deteriorated.
A case has been registered on the basis of a complaint by the student's father, and an investigation is on, Binjharpur police station inspector in-charge Amarendra Dash said.
According to the hospital authorities, the student is now stable, he added.
(With inputs from PTI)