is this a good or bad essay topic...?

Remember the point of this essay: to give them a reason to say yes.

I think the symbolism in how you wear your hair is a great twist on a familiar topic. I think it could make for an interesting read.

But most of all, I think you should ABSOLUTELY take the word of your teacher, who does this all day long, year after year, over that of a bunch of strangers (myself included) on the internet.