I once got dinged by a section leader in a chemistry class for referring to "pouring 50 ml of (something-or-other) from a graduate." His comment was "You poured from a graduated cylnder. I am a graduate!"
Here is a picture of a graduated cylinder, a device for measuring precise amounts of liquids: http://makeashorterlink.com/?E52921ECB

At the risk of belaboring the obvious - you didn't graduate from school, you were graduated from the school, making you a graduate of that school.

(But that may be fighting a lost battle, like trying to insist that "loan" is a noun...Can't you imagine? Mark Antony addressing the Roman populace: "...countrymen - LOAN ME YOUR EARS!")