Kouchou-sensei to Kujira
Genres: Drama
Type: Movie, Episodes: 1
Aired: 2007
Source: Unknown
Rating: G - All Ages
Synopsis:
A seaside school. In the corridor stands the principal, beloved of the high-spirited youngsters. Gazing at a picture of a whale drawn as a child, the head teacher is swept away with sentiment into a flashback from the past. Just then, on the ocean horizon... 

(Source: Official site)