A double "E" is a Geek. The etymology becomes obvious after you remove the G and the K.
This came out of a Schoolastic catalog ad for a Lizzie McGuire book. The cartoon version of Lizzie is seen saying "Don't be a double 'E'."
I had to ask my 8 year-old daughter what the hell it meant, so this is cutting-edge slang folks.
Two 5th graders in the playground:
Tyrone: Hey Brad, want some Mary Jane?
Brad: No. My parents said I shouldn't do that.
Tyrone: Jesus Brad! Don't be a double "E!" I suppose you don't drink either. What a dw"ee"b.
(here we see that many nerd pejoratives feature the double "E")
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