COOL!

Check it out! There is a ring tone that adults can't hear, which is being used by teenagers to pass messages in class. Go to RING TONE to read the article. This article makes me very curious as to when we start losing our ability to hear higher frequencies and, specifically, what part of the ear begins to degenerate. If anyone finds out please let me know! Thanks.

UPDATE: I guess I'm not an adult because a friend just sent me the special tone and I could hear it. Though it was really soft, so I could see how in a classroom it could be missed by the teacher.