Kinpachi-sensei (3年B組金八先生, San-nen B-gumi Kinpachi-sensei) is a Japanese television drama that aired from 1979 to 2011. The official English title is Mr. Kinpachi in Class 3B. Kinpachi-sensei tells the story of a third-year junior high school class in Japan; its teacher is Kinpachi Sakamoto, played by Tetsuya Takeda. The series has a lot of social commentary on issues such as homosexuality, gender dysphoria, and psychological pregnancy, as well as bullying (of both students and teachers), teenage pregnancy, teenage suicide, hikikomori, and the extreme pressure to do well in school.

The series began in 1979, a pivotal year when issues such as delinquency and on campus violence reached a fever-pitch amongst the educational spectrum; "Kinpachi-sensei," portrayed by former singer Tetsuya Takeda of Kaientai fame, attempts to resolve such problems using a blend of charisma, honesty, humor and wit.