Various museums across the US are participating in free admission on Saturday, 25 Sept 10. The link below takes you to a searchable site. The Florida Air Museum in Lakeland is one of the museums participating that my family will be visiting.
Other aviation museums I saw were:
Atomic Testing Museum
CAF Airpower Museum
College Park Aviation Museum
The Museum of Flight
The National World War II Museum
U.S. Space & Rocket Center
USS Alabama Battleship Park
Enjoy free general admission for you and a guest to hundreds of museums and cultural venues nationwide on Saturday, September 25. 2010.