Monster Story
A storyteller frightens campers with a function that is continuous everywhere but differentiable nowhere, like the Weierstrass function.
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Free for classrooms, worksheets, slides and other non-commercial use under CC BY-NC 4.0, with credit to Ben Orlin.
Cartoon by Ben Orlin, Math with Bad Drawings. https://cartoons.mathwithbaddrawings.com/2017-05-25-monster-story/ (CC BY-NC 4.0)Transcript
Storyteller (at a campfire): "It was continuous everywhere... and differentiable NOWHERE!"
[Caption] "Math Monster Stories"