I am a new member with a question regarding schooling. How might I learn where my great grandfather an MD, went to medical school? I know his dates and locations, but don't know where to begin this search.
I would suggest searching for an obituary for him first off. Often this source will reveal the educational background relating to a particular school might be noted. Sadly there is no master index of all known medical school graduates. We do have a book called the The Deceased Physicians Directory (1804-1929). If he died after 1929, the following address may assist you further for your great-grandfather. They maintain an archives for the American Medical Association at this facility.
The National Library of Medicine
History of Medicine Division
Building 38, Room 1E-21
8600 Rockville Place
Bethesda, Maryland 20894