CensusAtSchool is a national, biennial project run by the University of Auckland's
Department of Statistics that shows children the relevance of statistics to everyday life.
In class, Year 5 to Year 13 students, aged 9 to 18, use digital devices to answer 35 online questions in English or te reo Maori, providing a unique snapshot of Kiwi childhoods.
So far, more than 10,000 students have taken part, and they have answered several questions on food.
The reason for the food questioning is, according to CensusAtSchool co-director Rachel Cunliffe, growing childhood obesity and much public debate over what children should be
eating at school.
She said an Education Review Office report released just before Easter found that most schools were doing a good job equipping young people to make good food choices, but acknowledged that factors such as family finances and attitudes, student price sensitivity and takeaway shops near schools could prevent children bringing or choosing good-quality lunches.
Cunliffe said she wondered if public discussions had raised parents' awareness of the importance of the school lunches they provide, and that this has led to more concerted efforts to provide packed lunches.
Cunliffe makes her two primary school-aged children daily packed lunches, and once a term they are allowed to buy lunch at school.
"Of course, they tell me that everyone else gets to buy their lunches 'all the time'," she said.
Cunliffe said over the past few years there had also been publicity around some school children going without breakfast or lunch.
She said she was "relieved" that the number of children reporting that they had no lunch was fewer than expected.
"That said, you don't want to think that any students are going hungry," she said.
"I am hoping that the 7 per cent of high-school students not having any lunch is because they didn't get their act together to prepare it.
"A packed lunch does take some forethought and preparation."
The census also asked children who brought packed lunches how many items grown at home were among the food provided that day. A quarter said they had at least one home-grown item in their lunchbox.
This year's edition of CensusAtSchool started on February 7.
Teachers can register their classes and take part at any time before it finishes on July 7.
The census is part of an international effort to boost statistical capability among young
people, and is carried out in Australia, the United Kingdom, Canada, the United States, Japan and South Africa.
The countries share some questions so comparisons can be made. In New Zealand, the Census started in 2003, and is run by the University of Auckland's Department of Statistics supported by Statistics NZ and the Ministry of Education.
Tuck shop lunches - what's on offer?
The Herald took a look at a handful of school tuck shop menus published online to see what options were available for hungry Kiwis.
Many schools publish their menus online to allow parents to see what their children can access for lunch.
Some schools have an online ordering system.
The term one menu for Swanson Primary School featured a mince and cheese pie or southern style chicken burger, toastie or nachos for $3.50; a hotdog with sauce, chicken noodles for $3 or a hash brown or sausage roll for $1.
They also had a selection of snacks including popcorn, cookies and muffins from 50 cents to $2.
Sacred Heart students could order oven baked potato wedges, a chicken sub, American hot dog, panini, a range of burgers or cold sandwiches for under $3.50.
Snacks included chips, cookies, muffins, donuts, slice and custard pie starting at $1.
The Sacred Heart tuck shop also had a breakfast menu with hash browns, spaghetti on toast, bacon and egg bagels or pizza bread starting at $1.
