"Our board of trustees and parents have done a wonderful job."
Parent and board member Matua Jayson had organised the putting down and lifting of the hāngī which was made possible with generous community donations including vegetables from Turners and Growers.
School registers from the early years of 1879 to 1905 had been brought out for the anniversary.
Many of the first pupils left school after standard 6 and went straight to work.
"We have found so many wonderful documents and photos in the archives," said Watson.
"There are photos of parents digging a hāngī pit in 1990 and some of them have grandchildren at the school now."
Mosston School now caters for children from years 1 to 6 and has a roll of around 160.