Simon: Yerim (Choerry)
Leah: Chenle (NCT)
Nick: Chaeyeon (Izone)
Abby: Heejin 
Bram: Hyejoo (Olivia Hye)
Garret: Sooyoung (Yves)
Mr. Worth: JYP (Park Jinyoung)
Ethan: Miya (GWSN) 
Martin: Nancy (Momoland)
Nora Spier: Park Jisung (NCT) 
Emily Spier: Kim Hyuna 
Jack Spier: Kim Hyojong
Ms. Albright: Haseul
Cal: Rosie (Blackpink)
Lyle: Yeji (Itzy)
Taylor: Sana (Twice)
Jackie (first boyfriend): Jaemin (NCT)
Math Teacher: Kwon Eunbi (Izone) 

Tumblr users and email 
Yerim: @VeryVeryChoerry --> RayOfSunshine - LoveChoerryMotion
Chenle: @ChenChen01 
Chaeyeon: @MiyawakiChaeyeon
Heejin: @Heekkie 
Hyejoo: @OliviaColumbia - @Egoist01 
Sooyoung: @Swan_Yves 
Jisung: @nctJisung