This has puzzled me for years, and I finally decided to try to find the answer.  Lo and behold, I don’t know how to search for the answer.  Here’s the question.

I attended high school.  I went to high school, and eventually graduated FROM high school.  I no longer went to high school.

I keep hearing people say “I graduated high school” or “she graduated high school”.  I wonder if they took English along the way, and yet I do know what they mean and it may be an accepted verbal formulation.   How would one find out?

I happen to believe that simply because some language can accurately convey a meaning doesn’t necessarily excuse it’s use.  ”I done that”, “No, you be there, I seen you”, are examples.

Any thoughts?