COSI here has two holograms against the wall. The other one is of a pen.

2nd Floor

Go to the Museum's Attic.

Go to the presidents' display (and toward the Free Enterprise, Crime, Water Wonders, and Planetarium sections).

Walk into the Street of Yesteryear.

Go to the Cracker Jack Display.

Other Floors

Take the steps and head toward the 1st floor.

Take the steps up to the 3rd floor (by the bees).