This year they chose the Mental Health Foundation (MHF) for its work with Farmstrong, a joint venture founded by the MHF and rural insurer FMG to promote wellbeing for farmers.
"We had a class vote on which charity to donate to this year and the MHF and Farmstrong came up tops. There is a high suicide rate among vets and organisations like the MHF and Farmstrong are helping raise awareness around suicide prevention."
The rest of the money will go towards celebrating Halfway Day in July, a day that marks the half-way point of the five-year vet degree.
"We will head to Taupo and have a big class celebration."
Strategically placed animals and other items
Samantha says it was a little nerve-racking stripping down at first.
"But you have to put the scariness aside and get in and do it and have fun. It's for a good cause."
But don't expect the students to be completely starkers - there'll be the odd gumboot in sight.
This year's calendar was shot on a local farm and features strategically placed farm animals and other items.
"We have one month featuring dairy cows and another month with students pretending to shear sheep."
Samantha wasn't so nervous shooting her photo for the calendar as it was with her friends and flatmates.
"It was a bit scarier shooting the big class photo, but it was fun. It was a pretty interesting experience."
This year's calendar runs from July 2017 to June 2018 and will be available to buy at www.vetcalendar.co.nz from April (the website currently features last year's calendar but will be updated soon).
Keep an eye out for the vet calendar Facebook page, which will be created soon.
This article was originally published by the Mental Health Foundation and can be found here.