show-and-tell noun a public display and explanation US,1948 From the name of a school activity for young children.
I had ventured into a rest room at school, but not wanting to smoke dope, buy drugs, or converse with 20 robust fellows in Raiders jackets hosting a switchblade show-and-tell, I quickly turned around and left. — C.D. Payne, YouthinRevolt, p. 107, 1993