Your my hero mr teacher guy show her whose boss.

You're my hero, Mr. Teacher Guy. Show her(?) who's the boss. (via reddit)

Grammar is important. People who are bad at grammar are a thorn in the side of those of us who aren't, jabbing our eyeballs with painful darts of stupidity. 

On the other hand, self-righteous grammar nazis who don't know the difference between someone being playful and someone who is so dumb that they write in text-message language because they think it's acceptable are way worse, like 4 realz. Now, I do think that the teenager writing the sign (by the handwriting, I'm going with a girl) thought that she was being funny, but the way the sign ends reeks of a kid who thinks she's really gotten the better of someone.

According to redditor TheItalianChamp, who posted this photo, the teacher in question does actually teach English. In general, if the person making use of homophonic wordplay is your English teacher, even if you're the kind of person who can never let anything slide, leave it alone. They did it on purpose, and they will not only grade your sign harshly, they'll still be responsible for grading your papers in the future, and will probably not be so lenient about taking off points for a missing comma in the future.

(by Johnny McNulty)

Sources: redditor TheItalianChamp