The Dictionary of American Slang, Fourth Edition by Barbara Ann Kipfer, PhD. and Robert L. Chapman, Ph.D. Copyright (C) 2007 by HarperCollins Publishers. Cite This Source
show-and-tell in Technology
A visual dataflow language designed for use by elementary school children. ["A Visual Language for Keyboardless Programming", T. Kimura et al, TR WUCS-86-6, CS Dept Washington U, Mar 1986]. ["Show and Tell: A Visual Language", T.D. Kimura et al in Visual Programming Environments: Paradigms and Systems, E.P. Glinert ed, IEEE Comp Sci Press, 1990, pp. 397-404]. (1995-01-31)
A public presentation or display, as in It was a terrible bore, what with their show and tell of every last detail about their trip around the world. This expression originated in the 1940s to describe a learning exercise for young children, in which each child in a group brings some object to show the others and talks about it.