The attackers allegedly broke down the gate of her school where she was sitting and talking to her husband after finishing classes on Thursday afternoon.
Her husband had locked the gate when the men asked to enter the school, said Betagi Police Station OC Mamun-ur-Rashid.
The men broke the padlock and started beating the teacher's husband and eventually locked him in one of the classrooms.
They then took the victim to another room and took turns to rape her before fleeing the scene, the teacher said in the police case she started on Thursday night.
The case accuses Sumon Biswas, 35, 'Rasel', 24, Sumon Kazi, 30, 'Rabiul', 18, 'Hasan', 25 and 'Jewel', 30.
The teacher, a Hindu woman, got married last year. Her husband is a resident of Nandi village of India's Purbo Medinipur district.
The police have taken to her to Borguna Sadar Hospital for a medical examination, said OC Mamun.
He said the police are trying to arrest the suspects.