Demonstrate swapping variables' values by swapping the contents of two cups full of liquid; you need a third cup to swap the liquids just like you need a third, temporary, variable to swap the values.

Student’s often struggle with swapping the values of two variables.
Using two cups full of liquid, it’s easier for students to see why you can’t just swap values without a third, temporary container.
This method helps students visualize what they need to do and why!

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