Students hypothesize whether vinegar and ammonia-based glass cleaner are acids or bases. They create designs on index cards using these substances as invisible inks. After the index cards have dried, they apply red cabbage juice as an indicator to reveal the designs.

Students learn the basics of acid/base chemistry in a fun, interactive way by studying instances of acid/base chemistry found in popular films such as Harry Potter and the Prisoner of Azkaban and National Treasure. Students learn what acids, bases and indicators are and how they can be used, including invisible ink. They also learn how engineers use acids and bases every day to better our quality of life. Students' interest is piqued by the use of popular culture in the classroom.

Students explore the properties of composites using inexpensive materials and processing techniques. They create beams using Laffy Taffy and water, and a choice of various reinforcements (pasta, rice, candies) and fabricating temperatures. Student groups compete for the highest strength beam. They measure flexure strength with three-point bend tests and calculations. Results are compared and discussed to learn how different materials and reinforcement shapes affect material properties and performance.

Using gumdrops and toothpicks, students conduct a large-group, interactive ozone depletion model. Students explore the dynamic and competing upper atmospheric roles of the protective ozone layer, the sun's UV radiation and harmful human-made CFCs (chlorofluorocarbons).

In this activity, students learn about their heart rate and different ways it can be measured. Students construct a simple measurement device using clay and a toothpick, and then use this device to measure their heart rate under different circumstances (i.e., sitting, standing and jumping). Students make predictions and record data on a worksheet.

Lighting is responsible for nearly one-third of the electricity use in buildings. One of the best ways to conserve energy is to make sure the lights are turned off when no one is in a room. This process can be automated using motion sensors. In this activity, students explore material properties as they relate to motion detection, and use that knowledge to make design judgments about what types of motion detectors to use in specific applications.

The study of biomimicry and sustainable design promises great benefits in design applications, offering cost-effective, resourceful, non-polluting avenues for new enterprise. An important final caveat for students to understand is that once copied, species are not expendable. Biomimicry is intended to help people by identifying natural functions from which to pattern human-driven services. Biomimicry was never intended to replace species. Ecosystems remain in critical need of ongoing protection and biodiversity must be preserved for the overall health of the planet. This activity addresses the negative ramifications of species decline. For example, pollinators such as bees are a vital work force in agriculture. They perform an irreplaceable task in ensuring the harvest of most fruit and vegetable crops. In the face of the unexplained colony collapse disorder, we are only now beginning to understand how invaluable these insects are in keeping food costs down and even making the existence of these foods possible for humans.

Students learn about material properties, and that engineers must consider many different materials properties when designing. This activity focuses on strength-to-weight ratios and how sometimes the strongest material is not always the best material.

Students toss coins to determine what traits a set of mouse parents possess, such as fur color, body size, heat tolerance, and running speed. Then they use coin tossing to determine the traits a mouse pup born to these parents possesses. Then they compare these physical features to features that would be most adaptive in several different environmental conditions. Finally, students consider what would happen to the mouse offspring if those environmental conditions were to change: which mice would be most likely to survive and produce the next generation?

Bernoulli's principle relates the pressure of a fluid to its elevation and its speed. Bernoulli's equation can be used to approximate these parameters in water, air or any fluid that has very low viscosity. Students learn about the relationships between the components of the Bernoulli equation through real-life engineering examples and practice problems.

Students use the scientific method to determine the effect of control surfaces on a paper glider. They construct paper airplanes (model gliders) and test their performance to determine the base characteristics of the planes. Then they change one of the control surfaces and compare the results to their base glider in order to determine the cause and effect relationship of the control surfaces.

When we look at the night sky, we see stars and the nearby planets of our own solar system. Many of those stars are actually distant galaxies and glowing clouds of dust and gases called nebulae. The universe is an immense space with distances measured in light years. The more we learn about the universe beyond our solar system, the more we realize we do not know. Students are introduced to the basic known facts about the universe, and how engineers help us explore the many mysteries of space.

Momentum is not only a physical principle; it is a psychological phenomenon. Students learn how the "Big Mo" of the bandwagon effect contributes to the development of fads and manias, and how modern technology and mass media accelerate and intensify the effect. Students develop media literacy and critical thinking skills to analyze trends and determine the extent to which their decisions may be influenced by those who manipulate a few opinion leaders. Note: The literacy activities for the Mechanics unit are based on physical themes that have broad application to our experience in the world concepts of rhythm, balance, spin, gravity, levity, inertia, momentum, friction, stress and tension.

Students explore the biosphere's environments and ecosystems, learning along the way about the plants, animals, resources and natural cycles of our planet. Over the course of lessons 2-6, students use their growing understanding of various environments and the engineering design process to design and create their own model biodome ecosystems - exploring energy and nutrient flows, basic needs of plants and animals, and decomposers. Students learn about food chains and food webs. They are introduced to the roles of the water, carbon and nitrogen cycles. They test the effects of photosynthesis and transpiration. Students are introduced to animal classifications and interactions, including carnivore, herbivore, omnivore, predator and prey. They learn about biomimicry and how engineers often imitate nature in the design of new products. As everyday applications are interwoven into the lessons, students consider why a solid understanding of one's environment and the interdependence within ecosystems can inform the choices we make and the way we engineer our communities.

In this multi-day activity, students explore environments, ecosystems, energy flow and organism interactions by creating a scale model biodome, following the steps of the engineering design process. The Procedure section provides activity instructions for Biodomes unit, lessons 2-6, as students work through Parts 1-6 to develop their model biodome. Subjects include energy flow and food chains, basic needs of plants and animals, and the importance of decomposers. Students consider why a solid understanding of one's environment and the interdependence of an ecosystem can inform the choices we make and the way we engineer our own communities. This activity can be conducted as either a very structured or open-ended design.

Students learn the fundamentals of using microbes to treat wastewater. They discover how wastewater is generated and its primary constituents. Microbial metabolism, enzymes and bioreactors are explored to fully understand the primary processes occurring within organisms.

Students examine the structure and function of the human eye, learning some amazing features about our eyes, which provide us with sight and an understanding of our surroundings. Students also learn about some common eye problems and the biomedical devices and medical procedures that resolve or help to lessen the effects of these vision deficiencies, including vision correction surgery.

Human beings are fascinating and complex living organisms a symphony of different functional systems working in concert. Through a 10-lesson series with hands-on activities students are introduced to seven systems of the human body skeletal, muscular, circulatory, respiratory, digestive, sensory, and reproductive as well as genetics. At every stage, they are also introduced to engineers' creative, real-world involvement in caring for the human body.

With a continued focus on the Sonoran Desert, students are introduced to the concepts of biomes, limiting factors (resources), carrying capacity and growth curves through a PowerPoint® presentation. Abiotic factors (temperature, annual precipitation, seasons, etc.) determine the biome landscape. The vegetative component, as producers, determines the types of consumers that form its various communities. Students learn how the type and quantity of available resources defines how many organisms can be supported within the community, as well as its particular resident species. Students use mathematical models of natural relationships (in this case, sigmoid and exponential growth curves) to analyze population information and build upon it. With this understanding, students are able to explain how carrying capacity is determined by the limiting factors within the community and feeding relationships. By studying these ecological relationships, students see the connection between ecological relationships of organisms and the fundamentals of engineering design, adding to their base of knowledge towards solving the grand challenge posed in this unit.