Ultimate Teacher(1988)

Kyoufu no Bio Ningen Saishuu Kyoushi

At a run down school the "Ultimate Teacher" Ganpachi is sent to get things back on track and prepare the delinquent students for the real world. But the students don't want Ganpachi ruining the gang they got going so their boss, Hinako, fights back Ganpachi aided by her secret power...her lucky kitty underwear. Things get more interesting when we findout Ganpachi is the result of genetic experiments.

(Source: Anime News Network)