Elsie said the wood was pre-cut but it was still a bit of a challenge hammering in the nails.
Ethan said he planned to build a desk also designed by Mari to go with his chair — "They are a really nice design".
Visitor programmes co-ordinator Mya Morrison-Middleton (Ngāi Tahu) said Mari was an Italian furniture designer.
"All his designs are free and open-source so anyone can make his designs and they can’t be traded or sold."
The educational workshop ran alongside the exhibition by Melbourne-based artist Emily Floyd called "Keeping it Complex, Keeping it Connected", which features furniture designed by Mari.
"They are simple but they are really structurally sound, they are really sturdy and they are also quite beautiful," Ms Morrison-Middleton said.
The exhibition runs until March 5.
