Stacking Graded Cubes

Safety

The smallest cube must not fit the small parts test cylinder (1.25 in. × 2.25 in.); a 4 cm cube does not.
Build on the floor, not a table, so a falling cube cannot drop onto feet.
Check the cubes for splinters and chipped corners before use.

1
Unroll a mat on the floor. Carry the cubes to the mat one at a time, the larger ones with two hands.
2
Place the cubes at random on the mat.
3
Look over the cubes, pick up the largest, and place it on the mat in front of you.
4
Find the next largest and place it in the center of the one below, lowering it slowly.
5
Continue to the smallest. Point of interest: the smallest cube going on top.
6
Look at the tower from the side. Take it down from the top, one cube at a time, and invite the child.
7
If the child knocks the tower down, let them rebuild it; if they only knock it down, put the cubes away and offer them another day.

A cube out of order hangs over the edge of the one below it, or the tower leans and falls.

The 3–6 Pink Tower has ten cubes with 1 cm steps. The toddler version uses four cubes with 2 cm steps, so each difference is easy to see.