Thinking the Box into Oblivion
Three stages: thinking inside the box, outside the box, and thinking the box itself into an impossible shape.
Use this cartoon
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/2019-11-07-thinking-the-box-into-oblivion/ (CC BY-NC 4.0)Transcript
Thinking INSIDE the box [thought bubble inside a wireframe cube] · Thinking OUTSIDE the box [bubble outside] · Thinking the box into OBLIVION [the cube inside the thought bubble, drawn as an impossible figure]