youcubed: Irrational Folding (9-12)
youcubed (Stanford University)

This activity is designed to give students the opportunity to explore, visualize, and create a representation of the relative lengths of the square roots from 1-10.

Illuminations: Stacking Squares
Illuminations (National Council of Teachers of Mathematics)

This lesson prompts students to explore ways of arranging squares to represent equivalences involving square- and cube-roots.