A Dunedin secondary school has criticised the timing of a strongly worded Government recommendation that schools require mask-wearing for the first four weeks of the new term.

The Ministry of Health and Ministry of Education gave notification last Thursday that it was "strongly recommended" for all schools to require pupils in Year 4 and above to wear masks in order to prevent the spread of Covid-19 and winter illnesses.

Logan Park High School co-principals Peter Hills and Kristan Mouat provided a joint statement to the Otago Daily Times yesterday, the first day of term 3.

School boards needed time to consider and make policy, and receiving the recommendation at the end of the school holidays was "unhelpful", the statement said.

"This late announcement added unnecessary stress to students, whānau, staff at the start of another challenging term."

The school was committed to keeping everyone well and had a "strong mask-wearing culture" while respecting those for whom wearing a mask was unsuitable.

Other schools in the South did not seem to find the timing of the notification a problem.

Mount Aspiring College principal Nicola Jacobsen said the issue had been on her mind since the end of last term.

The school strongly recommended mask-wearing as it was in the best interests of staff and pupils, she said.

This policy was announced to parents by email last week, receiving differing levels of support.

"As a school, we support anyone who can't wear a mask for whatever reason, that's fine, but last term we had significant disruption with staff and student illness."

Blue Mountain College principal Lindy Cavanagh-Monaghan said the challenge lay in keeping people wearing their masks.

For this reason, the four-week time period of the recommendation was a good idea.

"I think the majority of people are on board, but there's certainly a weariness that comes over time," she said.

Two staff members were currently away sick, she said.

"I'm hoping with the masks in place that can be one mitigating factor and we can keep disruption to a minimum."

Otago Primary Principals' Association president and Port Chalmers School principal Vicki Nicolson said the recommendation made little difference to the school, where mask-wearing was already standard practice.

Given the policy was not mandated, she was concerned colleagues might face backlash for promoting mask-wearing, but did not believe this was common in Otago.

"We all hate wearing masks, but I think we hate getting Covid more."

Otago Secondary School Principals' Association president and Otago Boys' High School rector Richard Hall said mask-wearing was already the standard among pupils and teachers.

The Government recommendation was "a sensible step", he said.

A mandate would have been helpful to deal with conflict over the issue, but as a whole the school community supported mask-wearing, he said.

Otago Boys' High School pupils Charlie Hore said although the masks had some drawbacks such as muffling speech, they also protected people.

"It's definitely worth it," Charlie said.

Unlike Charlie, fellow pupil Sam Gavin had already had Covid-19 and also believed wearing masks was the best approach.

"I'm used to it now because we've been wearing them for so long."