And then, finally, a grand classification between convex curved figures, concave curved figures, and crossed curved figures. All curves are on the left.
On the right, are various forms of polygons: convex, concave, and crossed.
The shapes underneath are geometry figures from the Cabinet of Shapes. The children would already know the names of these (from the Children’s House at about the age of four) but now, after all this practice and exploration, they are ready to classify plane figures!
No, really, it makes me dance with delight! How fun it this? And there is more!