Two-dimensional (2D) shapes are completely flat. They cannot be picked up. A polygon is a 2D shape with straight sides that meet at vertices. Polygons have names that show the number of sides they ...

Children should be provided with a large variety of shapes in a range of situations to stimulate learning. Nicole Weinstein suggests some ideas. Shapes are everywhere-regular and irregular, in 2D and ...

Big Idea – We can describe, measure, and compare spatial relationships. to build on students' knowledge of triangle and develop students' reasoning with properties of different classes of triangles to ...