Four students were killed and seven injured in Virudhunagar in Madurai district on Friday when their school's gate collapsed.
The students were swinging on the gate when it came off the hinges.
Three children died on the spot, while another succumbed to head injuries at the Government Rajaji Hospital in Madurai on Saturday morning.
The condition of two more students is stated to be serious.
The Virudhunagar police said it took more than an hour to pull the children out from under the collapsed gate.