Did you know that the Lancaster County Library system has a Family Museum pass program?!
Through this program you can get a FREE pass (for up to 4 people) to the Lancaster Science Factory, North Museum of Natural History & Science, National Watch and Clock Museum, Landis Valley Village & Farm museum, National toy train musuem, and the Ephrata Cloister and Hanns Her House and Museum!
Passes are available at all 17 public libraries in Lancaster County and even may be reserved online.
I have written an updated post on the Museum Pass program here.