Here Comes the Boom (2012) on Netflix

Back in his prime, Scott Voss (Kevin James) was a collegiate wrestler with some fairly impressive moves. Now, at 42, he teaches biology at troubled Wilkinson High School. Mr. Voss has begun to grow deeply indifferent in his role as an educator when a troubling announcement stirs him to action. Effective immediately, Wilkinson High will be eliminating all extracurricular activities. Suddenly, the most apathetic teacher on the staff has a reason to get involved. But how is a typical high-school teacher like Mr. Voss supposed to raise the $48,000 needed to save the music program from going belly up? Upon learning that some MMA fighters earn $10,000 just for stepping into the ring, Mr. Voss vows to get back in shape, and subject himself to a series of brutal beatings so his students won't have to go without.