Schools and early-childhood centres reopened their classrooms today for the first time in five weeks.
Only the children of people who could not work from home were allowed to attend, and principals said many schools had fewer students than expected.
The Ministry of Education had been told about 43,000 children would return.
It said by mid-morning it was confirmed that 7713 children were attending an early learning service and 11,846 were at school. However, not all schools and early learning services had reported by then.
Wellington's Berhampore School principal Mark Potter said six of the 14 children expected to attend had turned up.
He said some parents might have changed their minds, or decided to take their children to work with them.
"It looks like there should be more people and it's still a bit of a ghost town, so we're going to have to work quite hard to make sure the children who are on site don't feel isolated by being here."
Potter said the school would be organised into two separate classes with two teachers in each class.
The teachers would take turns working with the children in the classroom and then working with their regular students who were remote learning from home, he said.
"We think it will be doable for two weeks."
The Principals Federation and the Secondary Principals Federation said other schools also reported seeing fewer students than they had expected.
Secondary Principals Association president Deidre Shea said her own school, Onehunga High School, had 15 students today but had expected 20.
She said it was still worthwhile reopening the school.
"For those students that needed to be here, I think it was critical," Shea said.
"For some students, they're not able to be at home and those students need the opportunity to be able to continue to learn."
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