This resource uses text, images, maps and a laboratory exercise to explain how differences in the temperature and salinity of ocean water cause the formation of deep-ocean currents. It is part of the Jet Propulsion Laboratory's "Ocean Surface Topography from Space" website. This material is also available on the "Visit to An Ocean Planet" CD-ROM.

In this issue of the free online magazine, Beyond Penguins and Polar Bears, explore what the polar regions can teach us about the water cycle and the states and changes of matter. Find lesson plans about the many forms of water, ice, and snow found in the polar regions and how to use science notebooks to integrate literacy and science.

This article assembles free resources from the Water, Ice, and Snow issue of the Beyond Penguins and Polar Bears cyberzine into a unit outline based on the 5E learning cycle framework. Outlines are provided for Grades K-2 and 3-5.

This article highlights children's literature about states of matter, phase changes, the water cycle, and glaciers and icebergs for use in the elementary classroom.

Students will analyze the bond energy of the reactants and products in a chemical reaction. Students will develop a model to illustrate how the changes in total bond energy determine whether the reaction is endothermic or exothermic.

This classroom activity helps students understand how the angle of the Sun affects temperatures around the globe. After experimenting with a heat lamp and thermometers at differing angles, students apply what they learned to explain temperature variations on Earth. The printable six-page handout includes a series of inquiry-based questions to get students thinking about what they already know about temperature patterns, detailed experiment directions and a worksheet that helps students use the experiment results to gain a deeper understanding of seasonal temperature changes and why Antarctica is always so cold.