Texas Math Models

Try “number line” or “4.5D”

One shape, many names

the quadrilateral family

G3–4

A square is a rectangle AND a parallelogram AND a quadrilateral, all at once.quadrilateralparallelogramrectanglesquareeach ring inside adds one more rulesquare → rectangle  ✓rectangle → parallelogram  ✓rectangle → square  ✗the arrow runs from the special shape to the general onea rhombus is a parallelogram too“Is it a rectangle?” and “Is it a square?” are two different questions

How this one works

How

keep every name the shape still fits, not just the smallest one.

Best when

a question asks “which of these is it?” and more than one looks right.

The same problem, other ways