Sub-divisional Officer Rajesh Kumar said 150 odd children in that age group had come from different schools of the district to participate in an athletics championship to the Surajpura High School.
While the games was going on, around 57 children slipped out of the school and ate seeds from jatropha plants outside the school.
After some time, the children complained of stomach pain, vomiting and loose motion and were taken to the nearby primary health centre, the SDO said.
Jatropha seeds are used to manufacture bio-diesel.