Girls und Panzer der Film

In the wake of their victory in the national high school level competition, the girls return to their floating island home only to learn the worst possible news that they believed they had averted with their championship win. As the girls come to terms with the reality of their situation, a small hope arises that they cannot turn down. Led by their brilliant commander Miho Nishizumi, the girls seize the opportunity to avoid losing it all no matter the odds.

Synopsis from Anime News Network