Kyō no Go no Ni (今日の５の２, Kyō no Go no Ni?, lit. "Today's 5's 2" or "Today, in Class 5-2") is the debut Japanese seinen manga series created by Koharu Sakuraba, the author of Minami-ke. It was originally serialized in Kodansha's Bessatsu Young Magazine from 2002 to 2003, and the twenty-two chapters were later collected together in a single bound volume along with two extra chapters and published on November 11, 2003 by Kodansha. The main premise of Kyō no Go no Ni is the school life of the fifth grade class 5-2, focusing on an elementary-school boy named Ryōta Satō.

In 2006, Shinkūkan produced a five-episode original video adaptation (OVA) directed by Makoto Sokuza. The OVAs contain a special audio track in which the female characters' voices are replaced by members of the idol unit Sweet Kiss and were released in two versions: original and special edit. Xebec produced a thirteen episode anime adaptation directed by Tsuyoshi Nagasawa, unrelated to the OVAs. It first began airing on TV Tokyo between October 5, 2008 and December 28, 2008. Kodansha has announced that Xebec will be adapting an OVA version of the anime in 2009, directed by Tsuyoshi Nagasawa, featuring the same cast as the anime.

Source: Wikipedia