Geometry.

Geometry tasks can begin with a simple action: make a shape, turn it, or replace one piece with several others. The useful discussion concerns properties that stay the same and properties that change.

Pattern blocks and tangrams support composing regions. Geoboards foreground sides, vertices, and boundaries, while geometric shapes support sorting attributes and composing pictures.

Avoid making orientation part of a shape’s name. A square remains a square when rotated onto a corner. Invite learners to give reasons based on sides and angles, and to test a description using an unfamiliar example.