We’ve collected lots of references to papers, posters and reports that have been published that are about Unplugged, or make use of Unplugged. A key reference that was written around the 20th anniversary of the Unplugged project is the following, which gives a rather detailed history of the project and its philosophy:

Bell, T., Rosamond, F., & Casey, N. (2012). Computer Science Unplugged and related projects in math and computer science popularization. In H. L. Bodlaender, R. Downey, F. V Fomin, & D. Marx (Eds.), The Multivariate Algorithmic Revolution and Beyond: Essays Dedicated to Michael R. Fellows on the Occasion of His 60th Birthday (Vol. LNCS 7370, pp. 398–456). Heidelberg: Springer-Verlag, Berlin, Heidelberg.

The following 2018 reference is an updated survey of how CS unplugged has been used:

Bell, T., & Vahrenhold, J. (2018). CS unplugged—how is it used, and does it work?. In Adventures between lower bounds and higher altitudes (pp. 497-521). Springer, Cham.