flunk

verb5

1. •
   (US) Of a student, to fail a class; to not pass.

   • He flunked math, again.
2. •
   (US) To fail any challenge
3. •
   (US) Of a teacher, to deny a student a passing grade.

   • Unsatisfied with Fred's progress, the teacher flunked him.
4. •
   (US) To back out through fear. (Commonly in the phrase 'flunk it', the 'it' referring to a specific task avoided; sometimes without specific reference, describing a person's attitude to life in general.)
5. •
   (informal, old-fashioned) To shirk (a task or duty).