The condition of the children deteriorated after they were discharged from the Dataganj Community Health Centre last evening, Badaun District Magistrate Chandra Prakash Tripathi said.
They had been taken to the district hospital today and senior doctors were attending to them, he said.
The DM said, the in-charge of Dataganj health centre had been asked to explain why the students were discharged if they had not recovered fully.
While 25 students had to be admitted to the health centre, the rest were given first-aid.