The students were inside the structure when wind lifted it around 10- to 20-feet high at the school in Zillah, a city roughly 20 miles south of Yakima, the Yakima Herald reported.
Four students sustained minor injuries, including a possible concussion, Fire Chief Paul Stonemetz told the news outlet. He said that one other student received CPR and shock treatment and was airlifted to a hospital in critical condition.
Several local and state agencies responded to the scene. Stonemetz said it was not immediately clear whether the bounce house was secured to the ground when the students were playing on it.