[Free Registration/Login Required] This game challenges kids to sort objects by material. Taking their cues from the Three Little Pigs, preschoolers will sort items made of straw into one backpack, sticks into another, and bricks into a...

Lesson plan that helps students explore the attributes of polygons through the use of cooperative groups. Students use jigsaw puzzles and foldable polygons. They also connect the attributes of specific polygons with objects in the real...

The following unit can be used to teach measurable attributes. Students will describe and compare two objects with a measurable concept in common using direct comparison. Included are necessary vocabulary, a scavenger hunt, and links to...

Describes quasars as being classified within the category of an active galaxy. A description of the emergence of high-energy. Definitions of key words are provided.gamma-ray quasars as an important component of the gamma-ray sky.

Supernovae are divided into two basic physical types, including a description of supernova types and how they are classified based on the existence of hydrogen spectral lines. Definitions of key terms are provided.

This applet helps students visualize the shapes of shadows cast by a cube with a light coming from different angles. This helps students visualize shapes from different angles and to identify, sketch and classify the cross-sections of...

Richard Hamblyn tells the history of Luke Howard, the man who classified the clouds and forever changed humanity's understanding of these changeable, mysterious objects. [5:07]