This problem with multiple solutions offers an opportunity for students to practice simple addition and subtraction, work with number sentences (equations), and develop systematic work habits. Given cards containing the addition, subtraction and equal signs along with the digits 2, 4, 6, and 8. solvers are challenged to find as many ways as possible to arrange some or all seven cards to create true statements. The Teachers' Notes page offers suggestions for implementation, discussion questions, ideas for extension and support, printable cards (pdf) and a link to an interactive Flash applet.

This number challenge is an opportunity to reinforce mental arithmetic and order of operations while developing systematic work habits. Students are asked to use the numbers 4, 6, 6, and 8 (exactly once each) and the four basic operations to find as many ways as they can to represent the number 24. There are over 60 different ways! The Teachers' Notes page includes suggestions for implementation, discussion questions, ideas for support, and a link to a related article, Opening Out. (cataloged separately).

This video segment adapted from First Light explains why the highest peak in the Pacific, Mauna Kea, is an ideal site for astronomical observations. Featured are new telescope technologies that allow astronomers to explore the universe in more depth.

This segment from Swift: Eyes through Time traces the history military officers and engineers discovering a strange phenomenon in the sky that astronomers now know are gamma-ray bursts.

In this video segment, the ZOOM cast demonstrates how to use cabbage juice to find out if a solution is an acid or a base.

In this video segment adapted from ZOOM, two cast members demonstrate what happens when vinegar is added to baking soda inside a container. The resulting chemical reaction produces enough carbon dioxide to launch their paper rocket skyward.
Recommended for: Grades K-5

A car propelled by the reaction between lemon juice and baking soda has more in common with rockets and jet aircraft than one might think. In this video segment adapted from ZOOM, two cast members demonstrate the power of rocket-propelled vehicles and how to exploit the force produced by the carbon dioxide gas. Grades 3-8.

It would seem that bottles of lemon juice and rockets have only their basic shape in common. However, as two cast members from ZOOM demonstrate in this adapted video segment, when baking soda is added to the mix, a plastic bottle can act very much like a real rocket. Grades 3-8.

In this video from Nature, geological detectives use ancient diamonds to learn more about Earth's inner layers.

In this video segment adapted from ZOOM, cast members make their own hovercraft and demonstrate how the air leaking out of a balloon can make a plastic plate hover above a table.

In this informational text, elementary school readers learn about the difference between weather and climate and about components of the climate system. The text can be used to practice visualizing and other comprehension strategies. Available in K-2 and 3-5 grade bands and as an illustrated book as well as a text document, the story appears in the online magazine Beyond Weather and the Water Cycle.

Watch alpha particles escape from a polonium nucleus, causing radioactive alpha decay. See how random decay times relate to the half life.

Use aluminum foil, salt water, and activated charcoal to construct a simple battery strong enough to power a small motor or light.

This article highlights resources related to water from the American Museum of Natural History and at-home activities on ice and water.

In this problem learners practice addition, subtraction and multiplication while developing logical reasoning. Solvers apply the given clues along with their understanding of the domino numbering system to determine which dominoes are missing from a set. The Teachers' Notes page includes suggestions for implementation, discussion questions, ideas for extension and support, printable sheets of dominoes (pdf), and a link to an interactive Dominoes Environment (cataloged separately).

Find out how angles and symmetry come into play in the game of pool in this video adapted from Annenberg Learner’s Learning Math: Measurement.

This video segment adapted from NOVA explains why ice sheets move. To find out how fast they move, scientists carve a tunnel through a glacier.

What would happen if a portion of the Antarctic Ice Sheet were to melt? This video segment adapted from NOVA uses animations to show the effect of a 6-meter sea-level rise on coastal cities across the world.

What happens when the ground under your feet is ice and it's moving? This video segment adapted from NOVA features some of the dangers faced by scientists conducting research in Antarctica.

This video segment adapted from NOVA uses microwave images to reveal how sea ice doubles the size of Antarctica each winter. Rare footage shows how sea ice crushed the famous ship Endurance in 1914.