Care to let us know what Mensa is?
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Well, if you are an active member of Mensa, you can tell the college what you have done with the organization. They will value it if you do so. You can also take advantage of your membership and ask for letters of recommendation of other Mensa member that you know. If you only state that you are a member of Mensa they are not going to care a lot.
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No. Most people will be jealous and get defensive at the idea that you are probably smarter than they are.

If you are involved, you can describe the work you’ve done, but you certainly don’t want to list it just to show you are intelligent. People get very insecure about that.
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am a member

Probably not, but knowing you’re a member can give your adviser something to preach about if your grades are mediocre.
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