While we know air exists around us all the time, we usually do not notice the air pressure. During this activity, students use Bernoulli's principle to manipulate air pressure so its influence can be seen on the objects around us.

This lesson is an exciting conclusion to the airplanes unit that encourages students to think creatively. After a review of the concepts learned, students will design their own flying machine based on their knowledge of the forces involved in flight, the properties of available materials, and the ways in which their flying machine could benefit society. Students will also learn how the brainstorming process helps in creative thinking and inventing and that scientists and engineers use this technique to come up with new products or modify and improve exiting products.

Pump gas molecules to a box and see what happens as you change the volume, add or remove heat, change gravity, and more. Measure the temperature and pressure, and discover how the properties of the gas vary in relation to each other.

Students work as engineers and learn to conduct controlled experiments by changing one experimental variable at a time to study its effect on the experiment outcome. Specifically, they conduct experiments to determine the angular velocity for a gear train with varying gear ratios and lengths. Student groups assemble LEGO MINDSTORMS(TM) NXT robots with variously sized gears in a gear train and then design programs using the NXT software to cause the motor to rotate all the gears in the gear train. They use the LEGO data logging program and light sensors to set up experiments. They run the program with the motor and the light sensor at the same time and analyze the resulting plot in order to determine the angular velocity using the provided physics-based equations. Finally, students manipulate the gear train with different gears and different lengths in order to analyze all these factors and figure out which manipulation has a higher angular velocity. They use the equations for circumference of a circle and angular velocity; and convert units between radians and degrees.

A gear is a simple machine that is very useful to increase the speed or torque of a wheel. In this activity, students learn about the trade-off between speed and torque when designing gear ratios. The activity setup includes a LEGO(TM) MINDSTORMS(TM) NXT pulley system with two independent gear sets and motors that spin two pulleys. Each pulley has weights attached by string. In a teacher demonstration, the effect of adding increasing amounts of weight to the pulley systems with different gear ratios is observed as the system's ability to lift the weights is tested. Then student teams are challenged to design a gear set that will lift a given load as quickly as possible. They test and refine their designs to find the ideal gear ratio, one that provides enough torque to lift the weight while still achieving the fastest speed possible.

Students are introduced to the idea of electrical energy. They learn about the relationships between charge, voltage, current and resistance. They discover that electrical energy is the form of energy that powers most of their household appliances and toys. In the associated activities, students learn how a circuit works and test materials to see if they conduct electricity. Building upon a general understanding of electrical energy, they design their own potato power experiment. In two literacy activities, students learn about the electrical power grid and blackouts.

This activity is an easy way to demonstrate the fundamental properties of polar and non-polar molecules (such as water and oil), how they interact, and the affect surfactants (such as soap) have on their interactions. Students see the behavior of oil and water when placed together, and the importance soap (a surfactant) plays in the mixing of oil and water which is why soap is used every day to clean greasy objects, such as hands and dishes. This activity is recommended for all levels of student, grades 3-12, as it can easily be scaled to meet any desired level of difficulty.

Students investigate motors and electromagnets as they construct their own simple electric motors using batteries, magnets, paper clips and wire.

In this activity students practice measuring techniques by measuring different objects and distances around the classroom. They practice using different scales of measurement in metric units and estimation.

This hands-on activity explores five different forms of erosion (chemical, water, wind, glacier and temperature). Students rotate through stations and model each type of erosion on rocks, soils and minerals. The students record their observations and discuss the effects of erosion on the Earth's landscape. Students learn about how engineers are involved in the protection of landscapes and structures from erosion. Math problems are included to help students think about the effects of erosion in real-world scenarios.

Students explore the use of wind power in the design, construction and testing of "sail cars," which, in this case, are little wheeled carts with masts and sails that are powered by the moving air generated from a box fan. The scientific method is reviewed and reinforced with the use of controls and variables, and the engineering design process is explored. The focus of the activity is on renewable energy, as well as the design, testing and redesign of small cars made from household materials. The activity (and an extension worksheet) includes the use of kinematic equations using distance, time traveled and speed to enforce exponents and decimals.

Students build and observe a simple aneroid barometer to learn about changes in barometric pressure and weather forecasting.

Using plastic straws, wire, batteries and iron nails, student teams build and test two versions of electromagnets one with and one without an iron nail at its core. They test each magnet's ability pick up loose staples, which reveals the importance of an iron core to the magnet's strength. Students also learn about the prevalence and importance of electromagnets in their everyday lives.

This lesson introduces students to the concepts of air pollution and technologies that have been developed by engineers to reduce air pollution. Students develop an understanding of visible air pollutants with an incomplete combustion demonstration, a "smog in a jar" demonstration, construction of simple particulate matter collectors and by exploring engineering roles related to air pollution. Next, students develop awareness and understanding of the daily air quality and trends in air quality using the Air Quality Index (AQI) listed in the newspaper. Finally, students build and observe a variety of simple models in order to develop an understanding of how engineers use these technologies to clean up and prevent air pollution.

Students learn about energy flow in food webs, including the roles of the sun, producers, consumers and decomposers in the energy cycle. They model a food web and create diagrams of food webs using their own drawings and/or images from nature or wildlife magazines. Students investigate the links between the sun, plants and animals, building their understanding of the web of nutrient dependency and energy transfer.

Students learn about energy and nutrient flow in various biosphere climates and environments. They learn about herbivores, carnivores, omnivores, food chains and food webs, seeing the interdependence between producers, consumers and decomposers. Students are introduced to the roles of the hydrologic (water), carbon, and nitrogen cycles in sustaining the worlds' ecosystems so living organisms survive. This lesson is part of a series of six lessons in which students use their growing understanding of various environments and the engineering design process, to design and create their own model biodome ecosystems.

Students gain an understanding of the difference between electrical conductors and insulators, and experience recognizing a conductor by its material properties. In a hands-on activity, students build a conductivity tester to determine whether different objects are conductors or insulators. In another activity, students use their understanding of electrical properties to choose appropriate materials to design and build their own basic circuit switch.

Visualize the gravitational force that two objects exert on each other. Change properties of the objects in order to see how it changes the gravity force.

In a multi-week experiment, student groups gather data from the photobioreactors that they build to investigate growth conditions that make algae thrive best. Using plastic soda bottles, pond water and fish tank aerators, they vary the amount of carbon dioxide (or nutrients or sunlight, as an extension) available to the microalgae. They compare growth in aerated vs. non-aerated conditions. They measure growth by comparing the color of their algae cultures in the bottles to a color indicator scale. Then they graph and analyze the collected data to see which had the fastest growth. Students learn how plants biorecycle carbon dioxide into organic carbon (part of the carbon cycle) and how engineers apply their understanding of this process to maximize biofuel production.