Quiz Magic Academy: The Original Animation 2

Following the destruction of the magical floating device from OVA 1, the Magic Academy falls to earth, but unfortunately lands on and breaks a demon seal, releasing hundreds of ancient demons into the forest around the academy. The teachers are barely keeping the demons away and are desperately searching for the pieces of the floating device, so to earn more magic stones, all of the students from Amelia's class decide to leave the academy (even though they were told not to) to find the missing pieces.

(Source: ANN)