Sarah Jessica Parker helps Elmo understand the concept of a pair. She uses shoes, mittens, and ice skates to define a pair. This video could be used before a math lesson to define this concept.

Zoe and Big Bird define the concept of the same and different by comparing themselves. They identify the ways they are the same and the ways they are different. This video could be used as an introduction to comparing objects.

Focus on classification using this resource. A young girl demonstrates how to sort and classify objects by cleaning her room. It is a great way to link classroom learning to real life tasks.

Two hundred years before Mendeleev created the periodic table, scientists observed patterns in the elements and tried to sort them. The brief first video in a 15-part series explains the development of the periodic table and the many...