What Shape is a Grape - Sesame Street Author:Christy Webster Elmo, Grover, Zoe and their Sesame Street friends learn all about shapes while having a picnic in the park. — As they invite toddlers to help them identify circles, squares, rectangles, triangles, and more, they (and the reader) realize that the world around them is filled with every shape imaginableall it takes to find them is a little bit of lo... more »oking. Less common shapes such as octagons and rhombuses are defined in simple terms.