[Taken From AnimeNFO]

Based on Hisaichi ISHII`s comic strip Tonari no Yamada-kun, this film is about the daily lives of the Yamada family: Takashi and Matsuko (the father and mother), Shige (Matsuko`s mother), Noboru (the son), Nonoko (the daughter), and Pochi (the family dog). The comic is currently serialized in the Asahi Shinbun (see a sample of the comic), though it has been renamed Nono-chan.

Takahata wanted Yamada-kun to have the art style of watercolor pictures (see above) rather than cel pictures. To achieve that, the traditional paint-on-cel techniques were replaced with digital technology, making Yamada-kun the first Ghibli movie to be painted and animated entirely on computers.