The boy died at Bachpan School in Malkajgiri in Medchal district, police said.
Police said a school employee first saw a school bag floating in the sump. He then alerted other staff members and the school management informed the police. The body of Shiva Rachit was then recovered from the sump.
His parents, relatives and a large number of people gathered at the school and protested, blaming the school for negligence. They demanded immediate action against the management.
Police said a case has been filed and investigation is on.