The distribution of devices during lockdown was a "logistical nightmare" which meant some students did not get devices until lockdown was over, say Rotorua principals.
New Zealand Post has apologised for the delays and the Ministry of Education has acknowledged distribution of devices was not as fast as everyone would have liked.
The ministry sent 19,735 laptops or Chromebooks to school students in need nationwide during lockdown.
Some Rotorua principals say the ministry had good intentions when it committed to providing computers to families without them, but some were left waiting and wanting.
Rotorua Lakes High School staff rang every student to confirm their addresses and needs, principal Jon Ward told the Rotorua Daily Post.
More than 160 "lacked access" but were not a priority for the ministry because the school is Decile 5, not Decile 1-4.
This was "a significant blow" Ward said, because the schools served "a very disparate community".
The school resorted to reformatting and sending its devices.
Now students are back, the school is having "significant issues retrieving school devices" making teaching on-site more difficult, Ward said.
Rotorua Girls' High School principal Sarah Davis said some Year 13s only got computers in the final week before school reopened. Others got theirs last week - when they were back in class.
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"We were keen to get the girls with the biggest needs set up," Davis said.
"But there was a significant delay. A number of students couldn't do the work they wanted to do."
They are now "overwhelmed" by what's ahead of them.
"The other things we are still really unsure about are the university aspirations and what it will take to get into courses, and how their credits are going to be managed. There are quite a lot of solutions still to find out there."
Davis was concerned some Year 13s wouldn't return for the rest of their final year but the school "hasn't lost a single student" from this year group.
"I am so relieved that we have still got them here. That means we can keep working with them to get them where they should be."
Western Heights Primary School principal Brent Griffin said "the delivery of [information and communications technology] ICT was an incredibly ambitious ask".
"But obviously, getting it out was a logistical nightmare."
The 450-student school asked for 140 devices and last week many were still arriving after students had returned.
He said students who did have access to learning resources during lockdown made "great progress" and there was "really good engagement from families".
"I am really, really proud."
Westbrook School principal Colin Watkins said the ministry was "fantastic and supportive but the mechanisms were slow and cumbersome".
"Unfortunately, the delivery was less than adequate - in fact, it was dismal. Couriers were run off their feet," he said.
On the bright side, Watkins said the pandemic had brought the school community closer.
"Staff formed stronger bonds with families that we didn't have before.
"Students are more resilient, more confident, more mature and have better self-management skills than they did before lockdown."
Ōpōtiki College requested 109 devices for students but two weeks ago they had only received 21, deputy principal Robyn Abraham-Harris said.
Instead staff delivered more than 150 hard copy learning packs at alert level 3.
Staff phoned to collate students' needs "at short notice".
"Even then this is still not equitable because not all families have a cell phone, data or credit on phones.
"Not all students have an ideal situation to work from at home either, with many distractions or lack of a quiet space," she said.
One of the school's values is resilience and Abraham-Harris said rangatahi and whānau demonstrated this "in trying times".
"There are still plenty of challenges ahead. Inequity for Māori and rural learners is always an uphill battle."
The Ministry of Education's chief digital officer Stuart Wakefield said there had been "global [computer] supply shortages due largely to the pandemic".
"We acknowledge that the distribution of computers to students around New Zealand has not been as fast as everyone would like."
The ministry put "an initial focus on connecting students in senior secondary school working towards NCEA and those with the greatest need due to disadvantage".
"We have now been able to fulfil all computer requests for Years 11, 12 and 13 students in all deciles, apart from any new requests that may come in. The devices are configured and dispatched as quickly as possible after they are received from suppliers.
"To expedite delivery, we co-located a courier depot inside the warehouse where the computers are received, configured, boxed, labelled and given to the courier for distribution."
An NZ Post spokeswoman said the organisation apologised to customers who had experienced delays.
"When New Zealand moved to alert level 3 we received over 3.5 million parcels in the first two weeks and we are still receiving about 300,000 parcels a day, which is around Christmas levels.
"To put this into perspective, we're receiving on average over 200 parcels every minute."
She said some devices may have been delayed by up to two weeks because of an issue with addresses.
"We have been doing everything we can to get parcels delivered on time. We set up temporary processing sites, and are operating 11 sites 24/7 for the first time. We've brought on hundreds of extra vans and people, and are working around the clock to deliver items."