Spelunker Sensei
English name: Spelunker Is a Teacher
Genres: Comedy
Type: OVA, Episodes: 1
Aired: Mar 16, 2011
Studio: Studio PuYUKAI
Source: 4-koma manga
Rating: G - All Ages
Synopsis:
There's a new teacher in town—Spelunker! This unusual man is anything but a typical instructor, giving speeches about traffic safety to the students, reacting strangely to a humidifier, and enjoying lunch— albeit with ample condiment mishaps. With such a bizarre new role model to learn from, Spelunker's students will never be the same!

(Source: Anime-Planet)