Students follow the steps of the engineering design process as they design and construct balloons for aerial surveillance. After their first attempts to create balloons, they are given the associated Estimating Buoyancy lesson to learn about volume, buoyancy and density to help them iterate more successful balloon designs.Applying their newfound knowledge, the young engineers build and test balloons that fly carrying small flip cameras that capture aerial images of their school. Students use the aerial footage to draw maps and estimate areas.

Experiment with a helium balloon, a hot air balloon, or a rigid sphere filled with different gases. Discover what makes some balloons float and others sink.

Experiment with a helium balloon, a hot air balloon, or a rigid sphere filled with different gases. Discover what makes some balloons float and others sink.

Students explore static electricity by rubbing a simulated balloon on a sweater. As they view the charges in the sweater, balloon, and adjacent wall, they gain an understanding of charge transfer. This item is part of a larger collection of simulations developed by the Physics Education Technology project (PhET). The simulations are animated, interactive, and game-like environments.

Why does a balloon stick to your sweater? Rub a balloon on a sweater, then let go of the balloon and it flies over and sticks to the sweater. View the charges in the sweater, balloons, and the wall.

The purpose of this activity is to bring together the students' knowledge of engineering and airplanes and the creation of a glider model to determine how each modification affects the flight. The students will use a design procedure whereby one variable is changed and all the others are kept constant.

Students groups use balsa wood and glue to build their own towers using some of the techniques they learned from the associated lesson. While general guidelines are provided, give students freedom with their designs and encourage them to implement what they have learned about structural engineering. The winning team design is the tower with the highest strength-to-weight ratio.

Diphtheria has broken out in Nome, Alaska. Teams of sled dogs carry medicine 800 miles over snow and ice to prevent an epidemic. Everyone was brave but one dog, Balto, made the difference between failure and success.

In this video segment from Nature, researchers study pandas in an effort to halt their decline in population.

The purpose of this task is to provide students with a multi-step problem involving volume and to give them a chance to discuss the difference between exact calculations and their meaning in a context.

The purpose of this task is to provide students with a concrete situation they can model by dividing a whole number by a unit fraction.

Explore the origin of energy bands in crystals of atoms. The structure of these bands determines how materials conduct electricity.

Explore the origin of energy bands in crystals of atoms. The structure of these bands determines how materials conduct electricity.

In 1910, an international consortium of banks refinanced Haiti's international debt and took control of the country's treasury. In 1914, the bank refused to issue gold payments to the Haitian government and asked the U.S. military to protect the gold reserves. On December 17, 1914, U.S. marines landed in Haiti and moved the gold to the bank's New York vaults. Eight months later, the marines again landed in Port au Prince, Haiti's capital, this time claiming the need to protect foreign lives and property. They placed Port au Prince under martial law, ruthlessly subdued armed resistance in rural areas, and began training a new Haitian militia. Charlemagne Pralte led a resistance movement. In this "call to arms" and letter to the French minister, Pralte attacked President Wilson as a hypocrite for claiming to respect the sovereignty of small nations of Europe while occupying Haiti and urged Haitians to resist the Americans. (An English translation of the letter follows the French version.)

The beaded bandolier bag is a distinctive form created by American Indians in the Great Lakes and Plains regions beginning in the mid-19th century. These large, vividly colored and intricately beaded bags were a central element of men’s formal dress for dances and ceremonies.

This real world task requires students to answer questions about equations for calculating compound interest.

This task asks students to use similarity to solve a problem in a context that will be familiar to many, though most students are accustomed to using intuition rather than geometric reasoning to set up the shot.

This lesson explains leverage and insolvency and why it is good or bad. [Banking, Money, Finance playlist: Lesson 10 of 24]

This lesson provides an analysis of the federal reserve balance sheet as of February 2007. [Banking, Money, Finance playlist: Lesson 21 of 24]

This lesson discusses how open market operations effect the rate at which banks lend to each other overnight. [Banking, Money, Finance playlist: Lesson 14 of 24]