Up to 50 Palmerston North Boys' High School pupils and teachers were sent home on Friday after an outbreak of a stomach bug at the school's boarding facility.
The school's deputy rector, Gerard Atkin, told the Herald all students were well today, but two teachers remained sick.
He said he was unsure of the exact number of students hit by the outbreak, guessing "about 19".
However, rector David Bovey estimated 20 teachers and between 20 and 30 pupils were sick, Fairfax reported.
"A small number of boys missed exams," Atkin said.