The father of the girl had complained that a teacher from the school had allegedly outraged the modesty of his daughter by sending her an obscene message.
Aizawl district administration in its notice said that heavy rainfall has caused mudflow, landslides, rock falls, and other disruptions on key roads and locations in the district.
The state government has ordered the setting up of a Special Investigation Team (SIT) to probe the alleged sexual abuse of two female students.
All government and private schools in Udaipur have been ordered to remain shut until further orders in view of the law and order situation, Collector Arvind Poswal said.
The four-storey flagship school by the Delhi government will feature 72 smart classrooms, 11 advanced labs, a central library, and a multipurpose hall for 250 students.
All the other students were sent to their homes, the police said, adding that an investigation is underway.