Tetsuji Chūma
中馬 鉄治 Chūma Tetsuji
Nickname	Chū-san (チュウさん)
Age	33
Birthday	October 23
Gender	Male
Blood Type	B
Height	175 cm.
Weight	68 kg.
Hair	Black
Occupation	Chemistry Teacher
Relatives	Suzu Chūma (daughter)
Manga Debut	Chapter 1 Paint-Mask
Anime Debut	Episode 1 The Campus SKET
Seiyū	Hayato Nakata (Drama CD) Jōji Nakata (anime)

Tetsuji Chūma (中馬 鉄治, Chūma Tetsuji), more commonly called Chū-san, is a chemistry teacher at Kaimei High School and the homeroom teacher for class 2-C. He is the faculty sponsor for the Sket Dan, a fact he often uses to get them to do things for him. He frequently creates odd potions and explosives which oftentimes backfire. He is currently engaged to Remi.