At the National Comedy Center, the history of American comedy is on display: the museum’s artifacts include Joan Rivers’ stand-up notes, the Seinfeld “puffy shirt” and a George Carlin archive.

With every adult, two kids 17 and under can get into Jamestown’s National Comedy Center Museum and the Lucille Ball Desi Arnaz Museum for free. Purchased tickets are still required for adults.

As “Saturday Night Live” celebrates 50 years of being on air, the National Comedy Center in Jamestown, NY will preserve a collection of the show’s creative papers from the first five years ...