The children were admitted to a government hospital in Begusarai district and are said to be out of danger, a district official said.
The students complained of uneasiness after eating the meal at the Pidhauli middle school. Soon after, some children informed the school authorities that a dead lizard was found in the food.
Samples of the meal were collected by police.
The doctors who examined the children did not find any sign of poison in their bodies.
In the last eight months, dead lizards have been found in the mid-day meal at nearly a dozen schools across the state and dozens of children have fallen ill.