National Museum Day, sponsored by the the Smithsonian, is, as far as I can find, a day that occurs in September each year. So I recommend you enter into your calendar on September 1 as a recurring event to look this up. You can get a free pass for two by entering "Museum Day" in your browser - follow directions, and print your ticket for a museum near you. Enjoy! And please let me know how this experience worked for you!