Flying Colors (2015)

Flying Colors 2015 / ビリギャル 2015 / Flying Colours , Biri Gyaru, Flying Colors: How a Teen Girl Went from Academic Absurdity to an Elite University in One Amazing Year , Birigyaru , ビリギャル～学年ビリのギャルが1年で偏差値を40上げて慶應大学に現役合格した話 , Gal at the Bottom

Kudo Sayaka is a 2nd-grade high school student, a gal (Gyaru) who wears miniskirts and dyes her hair blonde. Even though she is a high school student, her actual academic grade level is on par with 4th-grade elementary school students. During the summer, Sayaka attends a private institution, where she meets Teacher Tsubota. Besides her mother, Teacher Tsubota is the first adult to praise her, and through his guidance and instruction, Sayaka begins to change.