Roxburgh Area School hosted almost 200 pupils from Millers Flat Primary School, Lawrence Area School, Tapanui Primary School, Heriot School, Blue Mountain College and the Roxburgh Health Camp School.
The event is designed to test problem-solving and teamwork skills by challenging pupils to make certain objects out of simple materials such as newspaper and sticky tape.
"It's an opportunity to provide fun in the curriculum," Roxburgh Area School principal Gary Pasco said.
Challenges included building a free-standing flagpole and raising a flag, building a bridge strong enough to hold a toy car and making a golf club.
Pupils were also given a challenge to do at home - to make some kind of clothing with a Scottish theme, to tie in with Roxburgh's Scottish Week celebrations.
Another home challenge was to make and decorate shortbread, which was judged on look, taste and presentation.