The Shadow Room was one of the science elements at Sesame Place from 1980 until (at least) 1999.
Shadow Wall image from The Herald News
A 1980 Christian Science Monitor article detailed the author's trip to Sesame Place. The Shadow Room was described as such:
We entered a chamber called the Shadow Room. Of all the playthings I sampled and saw, electronic and otherwise, this one most took my fancy. You stand against a blank wall in the semidarkness and an overhead strobe erupts with a sudden flash. You step away and your shadow is still there, temporarily and vividly pasted to the wall.
The Reading Eagle also described the attraction:
An article about the Texas Sesame Place said there was a two way mirror outside the Shadow Room so visitors (presumably parents of the kids in the room) could look inside the room.
The trick to The Shadow Room was a phosphorescent wall. Think of it as your standard glow in the dark material.
Kids lined up in front of the phosphorescent wall:
Image from BloggerA bright flash of light shines at the wall. The areas of the phosphorescent wall, that received the light, glow. The areas blocked by the kids create the shadow.
Image from Blogger
I believe it's used as a character changing area (since I have often seen Count and Zoe walk behind me as I sat with my son watching the show.)
Thanks to Jeff for the email. PLEASE email me if you have any memories of this or anything else at Sesame Place! You can find an email link in the sidebar on the left.