baka to test to shoukanjuu

Main article: List of Baka and Test characters

The story centers around a boy named Akihisa Yoshii, also known as the idiot or "Baka" of the titled anime. He attends Fumizuki Academy, a school where the staff rigidly divides the students based on the results of their academic scores. At the start of the school, students are academically sorted by entrance exam test grades. The higher the grades, the higher the class, and the better the benefits. In this case, Class A is filled with the highest-scoring students; therefore, their classroom was filled with many prestigious items (air conditioners, fancy seats, laptops, a free snack bar, etc.), while the state of Class F is the complete opposite of that, representing the "bottom of the barrel" amenities.

This academy has something special, where all the students manage to call forth Summoned Beings (Shōkanjū, or "Avatars" in the official English translation[2]). These Beings are used for battles between classes with the goal of capturing (or retaining) the best classroom facilities. Since Class A is filled with prodigies, they all have strong Summoned Beings, while Class F has drastically weak ones in comparison. A teacher must authorize/supervise each battle, and the health and strength of each summoned being is based on the student's last test score in that teacher's subject (i.e. Math, History, etc.). The beings lose points when struck by an opponent, and should the point count reach zero, the being and student are disqualified. However, if the student can leave the battle before reaching zero, these points can be replenished by taking a supplemental exam. The student's being may then return to the battle.

On the day of the placement test, an intelligent girl named Mizuki Himeji suffers from a fever and is unable to complete her test, hence her reigning in a score of zero. As a result, she is pigeonholed into Class F together with Akihisa Yoshii. Akihisa, who dreams of the day when the academy would no longer be divided by grades, pitches an idea to his class to rule over the higher-level classes by doing a Summoned Being War for both Mizuki's sake and to get more and more privileges. Aside from Mizuki (who happens to be the second-ranked student in the year), there is also the class representative Yūji Sakamoto, the bishōnen Hideyoshi Kinoshita, the perverted Tsuchiya Kouta, and the tomboyish Minami Shimada (who, as Akihisa claims, is his worst enemy).
Sources:http://en.wikipedia.org/wiki/Baka_and_Test

Akihisa Yoshii is the main protagonist and the narrator of the light novel series Baka to Test to Shokanjuu. He is portrayed as the "Ultimate Baka" and is said to have the worst grades of his entire class. Even because of his idiocy he was given the title of Punishment Inspector. Akihisa's parents are on long-term overseas work assignments and send money back regularly. So due to this Akihisa has gained excellent cooking skills.

Minami Shimada,She is strong and wild; according to herself, her hobby is "beating up Akihisa" and really does hit him all the time for whatever reason, but it's just a reverse way of displaying her special feelings for him. The so-called 'tsundere'. Whenever Akihisa's up to anything useless, she restricts him with excessive violence; and for this reason, Akihisa takes her as his natural enemy, thinking as if she really hates him a lot.

Yūji Sakamoto,Yūji has a laid-back attitude, which led him to not study at all for the placement test and, in turn, become part of Class F. However, after Shouko beat him in elementary history test, he is shown to be pulling his socks up as his grades where improved by leaps and bounds. Yūji also seems to have some cowardly and sadistic instincts, often bullying Akihisa. However, he can also be much kinder and compassionate. (Shown when he beat up the Tokonatsu duo and fighting with a guy for offending Shouko.)