Students measure the effectiveness of water filters in purifying contaminated water. They prepare test water by creating different concentrations of bleach (chlorine-contaminated) water. After passing the contaminated water through commercially available Brita® water filters designed to purify drinking water, students determine the chlorine concentration of the purified water using chlorine test strips and measure the adsorption of chlorine onto activated carbon over time. They graph and analyze their results to determine the effectiveness of the filters. The household active carbon filters used are one example of engineer-designed water purification systems.

Students learn about floods, discovering that different types of floods occur from different water sources, but primarily from heavy rainfall. While floods occur naturally and have benefits such as creating fertile farmland, students learn that with the increase in human population in flood-prone areas, floods are become increasingly problematic. Both natural and manmade factors contribute to floods. Students learn what makes floods dangerous and what engineers design to predict, control and survive floods.

Students learn about the importance of dams by watching a video that presents historical and current information on dams, as well as descriptions of global water resources and the hydrologic cycle. Students also learn about different types of dams, all designed to resist the forces on dams. (If the free, 15-minute "Water and Dams in Today's World" video cannot be obtained in time, the lesson can still be taught. See the Additional Multimedia Support section for how to obtain the DVD or VHS videotape, or a PowerPoint presentation with similar content [also attached].)

Students learn about the water cycle and its key components. First, they learn about the concept of a watershed and why it is important in the context of engineering hydrology. Then they learn how we can use the theory of conservation of mass to estimate the amount of water that enters a watershed (precipitation, groundwater flowing in) and exits a watershed (evaporation, runoff, groundwater out). Finally, students learn about runoff and how we visualize runoff in the form of hydrographs.

Students learn the history of the waterwheel and common uses for water turbines today. They explore kinetic energy by creating their own experimental waterwheel from a two-liter plastic bottle. They investigate the transformations of energy involved in turning the blades of a hydro-turbine into work, and experiment with how weight affects the rotational rate of the waterwheel. Students also discuss and explore the characteristics of hydroelectric plants.

Students use watt meters to measure the power required and calculate energy used from various electrical devices and household appliances.

Students apply everything they have learned over the course of the associated lessons about waves, light properties, the electromagnetic spectrum, and the structure of the eye, by designing devices that can aid color blind people in distinguishing colors. Students learn about the engineering design process and develop three possible solutions to the engineering design challenge outlined in lesson 1 of this unit. They create posters to display their three design ideas and the comparisons used to select the best design. Then, students create brochures for their final design ideas, and "sell" the ideas to their "client." Through this activity, students complete the legacy cycle by "going public" with the creation of their informative posters and brochures that explain their designs, as well as color blindness and how people see color, in "client" presentations.

Students are presented with a challenge question concerning color blindness and asked to use engineering principles to design devices to help people who are color blind. Using the legacy cycle as a model, this unit is comprised of five lessons designed to teach wave properties, the electromagnetic spectrum, and the anatomy of the human eye in an interactive format that introduces engineering applications and real-world references. It culminates with an activity in which student teams apply what they have learned to design devices that can aid people with colorblindness in distinguishing colors— as evidenced by their creation of brainstorming posters, descriptive brochures and short team presentations, as if they were engineers reporting to clients. Through this unit, students become more aware of the connections between the biology of the eye and the physical science concept of light, and gain an understanding of how those scientific concepts relate to the field of engineering.

Students learn about the types of waves and how they change direction, as well as basic wave properties such as wavelength, frequency, amplitude and speed. During the presentation of lecture information on wave characteristics and properties, students take notes using a handout. Then they label wave parts on a worksheet diagram and draw their own waves with specified properties (crest, trough and wavelength). They also make observations about the waves they drew to determine which has the highest and the lowest frequency. With this knowledge, students better understand waves and are a step closer to understanding how humans see color.

Building on an introduction to statics, dynamics free-body diagrams, combustion and thermodynamics provided by the associated lesson, students design, construct and test their own rocket engines using sugar and potassium nitrate an opportunity to apply their knowledge of stoichiometry. This activity helps students understand that the energy required to launch a rocket comes from the chemical energy stored in the rocket fuel. The performance of each engine is tested during a rocket launch, after which students determine the reasons for the success or failure of their rockets.

Students discuss the characteristics of storms, including the relationship of weather fronts and storms. Using everyday materials, they develop models of basic lightning detection systems (similar to a Benjamin Franklin design) and analyze their models to determine their effectiveness as community storm warning systems.

Students are introduced to the basics of the Earth's weather. Concepts include fundamental causes of common weather phenomena such as temperature changes, wind, clouds, rain and snow. The different factors that affect the weather and the instruments that measure weather data are also addressed.

Students begin this lesson by considering how weather forecasting plays an important part in their daily lives. They learn about the history of weather forecasting -- from old weather proverbs to modern forecasting equipment and how improvements in weather technology have saved lives by providing advance warning of natural disasters.

Students are introduced to some essential meteorology concepts so they more fully understand the impact of meteorological activity on air pollution control and prevention. First, they develop an understanding of the magnitude and importance of air pressure. Next, they build a simple aneroid barometer to understand how air pressure information is related to weather prediction. Then, students explore the concept of relative humidity and its connection to weather prediction. Finally, students learn about air convection currents and temperature inversions. In an associated literacy activity, students learn how scientific terms are formed using Latin and Greek roots, prefixes and suffixes, and are introduced to the role played by metaphor in language development. Note: Some of these activities can be conducted simultaneously with the air quality activity (What Color Is Your Air Today?) of Air Pollution unit, Lesson 1.

In this unit, students learn the basics about weather and the atmosphere. They investigate materials engineering as it applies to weather and the choices available to us for clothing to counteract the effects of weather. Students have the opportunity to design and analyze combinations of materials for use in specific weather conditions. In the next lesson, students also are introduced to air masses and weather forecasting instrumentation and how engineers work to improve these instruments for atmospheric measurements on Earth and in space. Then, students learn the distinguishing features of the four main types of weather fronts that accompany high and low pressure air masses and how those fronts are depicted on a weather map. During this specific lesson, students learn different ways that engineers help with storm prediction, analysis and protection. In the final lesson, students consider how weather forecasting plays an important part in their daily lives by learning about the history of weather forecasting and how improvements in weather technology have saved lives by providing advance warning of natural disasters.

Students conduct a simple test to determine how many drops of each of three liquids water, rubbing alcohol, vegetable oil can be placed on a penny before spilling over. Because of their different surface tensions, more water can be piled on top of a penny than either of the other two liquids. However, the main point of the activity is for students to come up with an explanation for their observations about the different amounts of liquids a penny can hold. To do this, they create hypotheses that explain their observations, and because middle school students are not likely to have prior knowledge of the property of surface tension, their hypotheses are not likely to include this idea. Then they are asked to come up with ways to test their hypotheses, although they do not need to actually conduct these tests as part of this activity.

Students are presented with the concepts of wetting and contact angle. They are also introduced to the distinction between hydrophobic and hydrophilic surfaces. Students observe how different surfaces are used to maintain visibility under different conditions.

Students discuss several human reproductive technologies available today pregnancy ultrasound, amniocentesis, in-vitro fertilization and labor anesthetics. They learn how each technology works, and that these are ways engineers have worked to improve the health of expecting mothers and babies.

Students are introduced to an important engineering element the gear. Different types of gears are used in many engineering devices, including wind-up toys, bicycles, cars and non-digital clocks. Students learn about various types of gears and how they work in machines. They handle and combine LEGO spur gears as an exercise in gear ratios. They see how gears and different gear train arrangements are used to change the speed, torque and direction of a power source. This prepares them to apply this knowledge in four associated activities in order to create successful solutions to design challenges that use LEGO MINDSTORMS(TM) NXT robots. A PowerPoint® presentation, pre/post quizzes and a worksheet are provided.

Through a series of three lessons and one activity, students are introduced to inertia, forces and Newton's three laws of motion. For each lesson, a combination of class demonstrations and PowerPoint® presentations are used to explain, show and relate the concepts to engineering. Lesson 1 starts with inertia, forces and Newton's first law of motion. Lesson 2 builds on lesson 1 with s review and then introduces Newton's second law of motion. Lesson 3 builds on the previous two lessons with a review and then introduces Newton's third law of motion. In a culminating activity, students apply their knowledge of forces, friction, acceleration and gravity in an experiment to measure the average acceleration of a textbook pulled along a table by varying weights, and then test the effects of friction on different surfaces.