In the US, why is ‘E’ skipped in grading is schools? Students can get A, B, C,D or F but not E, why?

Question

In the US, why is ‘E’ skipped in grading is schools? Students can get A, B, C,D or F but not E, why?

In: 875

Answer 1

I attended public school in the 1980s and there was definitely E for failing (59% correct or lower), F was not used.