高分低能

gāofēndīnéng
high in score but low in ability (as a result of teaching to the test)

CEDICT

  1. (education, of a student) high in score but low in ability
  2. high in score but low in ability

Wiktionary

Entry Composition

1 高分 gāofēn
  1. high marks
  2. high score
2 低能 dīnéng
  1. incapable
  2. incompetent
  3. stupid
  4. mentally deficient