I just had the greatest idea for teachers to build their own object collection, and include your students in the process! Have you ever played the game "Bigger or Better"? The idea of the game is to start everyone with the same simple object, say a pen or paper clip, and you progressively trade that item for something "bigger" or "better". Well, to build your collection, how about a version of the game called Time Machine! Where you give all your students the same simple object to start out with, say, a 2013 penny? And let them trade their item for something older, and more historical. You can give it a time limit, say a month or so, and then everyone brings in their objects to see who went the furthest back in time with the oldest item. You could even offer a fun prize for the oldest, or for the items that are from the time era you are teaching on. (Civil War, Colonial Times, etc) You could do it every year with every class, or even let two classes compete against each other for the coolest item!
I think it would be such a fun way to get everyone involved, opening their eyes to the historical treasures around them!