Operations were paralysed at Nyabururu High School in Kisii County on Sunday after parents flocked the institution to check on the condition of their children following reports of food poisoning.
They accused the school management of covering up the issue despite continued complaints of stomach pains from students.
Despite an assurance from the County Education director Pius Ng'oma that the matter is under control, the parents insisted on meeting their children.
"We are sorry about what might have happened but were are urging you to give us more time to handle the matter," Mr Ng'oma said, adding that the school would be closed if the situation worsens.
He said only 12 students were admitted at Nyangena Hospital because of fever and two had been discharged.
However, the Nation has established that a number of students raised concerns that they had been denied a chance to speak to their parents and were forced to attend classes despite the pain they were experiencing.
"We have been suffering for a long time now. The number of students who are sick is more than 200 but the management doesn't want to disclose the information," said one of the students.
"It's like we are in prison. The management is not ready to listen to our grievances," lamented another student.
A source who requested anonymity, however, attributed the food poisoning cases to the consumption of cabbages which were brought in two lorries last week.
The cabbages were later buried at the school farm.
The school administration denies the allegations.
"Let me request the media to be sensitive and fair on this issue. If there is a problem, there are relevant authorities to deal with it," said the school's principal Joyce Orioki.
The Kisii County government has promised to intervene in the matter.
"We received this information with a lot of concern. I promise that the county government will intervene and assist those in hospitals," said Sports executive Duke Mainga.