Why Your Child Thinks Squares Aren't Rectangles (And How to Fix It)
Your child points to a square and says: "That's a square. But that is a rectangle."
Then you rotate the square and they say: "Now it's a diamond!"
Here's the truth: This isn't a failure of attention. It's predictable from how kids learn shapes.
The Problem: Teaching Shapes as Pictures
Kids learn what shapes look like, not what must be true.
Research: Prototype-Based Reasoning
Kids develop mental templates. When rotated, they say "diamond" not "square".
But mathematically? All squares ARE rectangles.
The Shift: "What Must Be True?"
Properties are relationships among lines, not appearance.
How to Build This at Home
1. Ask "What Must Always Be True?"
Show rectangles in different orientations. Ask what's always true.
2. Use 6 Math Power Words
Unit, Compose, Decompose, Iterate, Partition, Equal.
3. Celebrate Mistakes
Ask "Tell me more. Did sides change when turned?"
4. Draw Same Shape 5 Ways
Normal, rotated, tiny, huge, tilted. Ask "All squares? How know?"
Your Move
Cut out square. Rotate it. Ask "Did sides change?" Watch lightbulb!