Why was that funny as a question? Widen your scope, ms. dirrty.
I graduated from high school in 1959, and university in 1964. Those of us that did that at that time still tend to say 'graduated from' instead of graduated high school - which has to do with different language use in different years.
You must get it by now that you are talking to people of different ages from around the world...
or if you don't, you should. A2k has quite a worldly reach (never mind age reach).