"A for effort" or "E for effort" - which is correct?

[Tafiti]

Had a heated debate about this at a bar last night - it was 2 against 2. I googled it, and found this explanation on Yahoo! Answers, but don't know if it's correct:

E for Effort came from US Government public service advertisements during World War 2. Employees were encouraged to increase productivity to support the war. One way to award productivity was a pin with the letter E.

I have an "E for Effort" pin that was given to my father.

Can anyone shed some light on this?

[Oeditpus Rex]

1. They're different contexts

'E' stands for effort, as in the example you've given. But one can get an 'A' for effort, as in "That's givin' it the old college try!"

[Tafiti]

2. I kind of figured

both were probably correct. We weren't sure if it was a regional thing because all 4 of us are from different states. I've always heard "E for effort", but I understand why "A for effort" makes sense. I just always thought saying E instead of A was just a patronizing, condescending, sarcastic, tongue-in-cheek way of conveying the same idea -- as in, I'm not even giving you a real letter grade, but I'll give you an E for effort.

[Ava]

3. i thought that when saying "a for effort"

(in an educational setting) it is a reference to the grade "a" and not to the first letter of effort