Stage Challenge judges said they were "blown away" by Whanganui High School's portrayal of the 2010 Pike River mining disaster.
Their production, 29 Below, won them first place in the regional contest held at Palmerston North's Regent on Broadway last Friday.
Event manager Hazel Reid said 29 Below was judged the best of the nine high school productions because of their commanding performance.
"Whanganui High School's performance really blew everyone away, addressing a brilliant theme - it was really powerful and fantastic."
And design judge Damian Thorne praised the school for their inspired performance.