Jung Jae-young

Kim Sang-nam

Yu Seon

Na Joo-won

Kang Shin-il

Vice Principal

장기범

Cha Myeong-jae

김혜성

Jang Dae-geun

조진웅

Charles

Kim Mi-kyeong

Principal Nun

Lee Hyun-woo

Kim Jin-man

지일주

Oh Chul-jin (uncredited)

김동영

Jo Jang-hyuk (uncredited)

Son Seung-won

Park Choong-nam (uncredited)

김호원

Goon San High Baseball Team

Chan-Hyeong Jo

Choong Joo Sung Sim School Baseball Team, Lee Cheol-Seung