12-sai.
English title: Age 12
Japanese title: 12歳。
Alternative titles: Juuni-sai.
Type: OVA
Source: Manga
Episodes: 8
Status: Finished Airing
Aired: Apr 3, 2014 to Jan 3, 2015
Duration: 11 min per ep
Rating: PG - Children
Studios: SynergySP, Ascension
Producers: Half H.P Studio
Genres: Romance
Themes: School
Demographics: Shoujo

The story begins with Hanabi, a sixth-grade girl who is neither an adult nor a child. She deals with issues such as accidentally witnessing her homeroom teacher kissing, and worrying about experiencing physiological changes before her friends. The manga depicts a 12-year-old girl's innocent worries and first love.

(Source: ANN)