Gakusei no Ryoubun(1983)

Gakusei no Ryoubun

A trio of "ordinary" high school boys, Takafumi, Akio, and Mitsuo, is joined by the half-Japanese Tadashi... They might seem like delinquents, but they are serious when it comes to love! In the end, they all have the same "students' responsibilities", as they face each day with youthful enthusiasm!

(Source: Hana to Yume, translated)

Note: Includes the one-shot Muromachi Senpuu (むろまち旋風)