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.

Students use ultrasonic sensors and LEGO© MINDSTORMS© NXT robots to emulate how bats use echolocation to detect obstacles. They measure the robot's reaction times as it senses objects at two distances and with different sensor threshold values, and again after making adjustments to optimize its effectiveness. Like engineers, they gather and graph data to analyze a given design (from the tutorial) and make modifications to the sensor placement and/or threshold values in order to improve the robot's performance (iterative design). Students see how problem solving with biomimicry design is directly related to understanding and making observations of nature.

Students learn about biomimicry and how engineers often imitate nature in the design of innovative new products. They demonstrate their knowledge of biomimicry by practicing brainstorming and designing a new product based on what they know about animals and nature.

Students are introduced to the concepts of biomimicry and sustainable design. Countless examples illustrate the wisdom of nature in how organisms are adapted for survival, such as in body style, physiological processes, water conservation, thermal radiation and mutualistic relationships, to assure species perpetuation. Students learn from articles and videos, building a framework of evidence substantiating the indisputable fact that organisms operate "smarter" and thus provide humans with inspiration in how to improve products, systems and cities. As students focus on applying the ecological principles of the previous lessons to the future design of our human-centered world, they also learn that often our practices are incapable of replicating the precision in which nature completes certain functions, as evidenced by our dependence on bees as pollinators of the human food supply. The message of biomimicry is one of respect: study to improve human practices and ultimately protect natural systems. This heightened appreciation helps students to grasp the value of industry and urban mimetic designs to assure protection of global resources, minimize human impact and conserve nonrenewable resources. All of these issues aid students in creating a viable guest resort in the Sonoran Desert.

By studying key processes in the carbon cycle, such as photosynthesis, composting and anaerobic digestion, students learn how nature and engineers "biorecycle" carbon. Students are exposed to examples of how microbes play many roles in various systems to recycle organic materials and also learn how the carbon cycle can be used to make or release energy.

How can you tell if harmful bacteria are in your food or water that might make you sick? What you eat or drink can be contaminated with bacteria, viruses, parasites and toxins—pathogens that can be harmful or even fatal. Students learn which contaminants have the greatest health risks and how they enter the food supply. While food supply contaminants can be identified from cultures grown in labs, bioengineers are creating technologies to make the detection of contaminated food quicker, easier and more effective.

This lesson begins with a demonstration prompting students to consider how current generates a magnetic field and the direction of the field that is generated. Through formal lecture, students learn Biot-Savart's law in order to calculate, most simply, the magnetic field produced in the center of a circular current carrying loop. For applications, students find it is necessary to integrate the field produced over all small segments in an actual current carrying wire.

Students read news reports and first-person accounts to imagine what it would be like to be in a blackout in a large city. They follow news reports as if the event were unfolding in real-time and keep weblogs or journals of their experience as they imagine it, taking on different roles of people who live in the city or commute there to work. They use their journal accounts to create a play or screenplay that depicts what the August 2003 blackout was like for the people in the U.S. and Canada who experienced it. Although this activity is geared towards fifth-grade and older students, it could be easily adapted for younger students.

Rockets need a lot of thrust to get into space. In this lesson, students learn how rocket thrust is generated with propellant. The two types of propellants are discussed and relation to their use on rockets is investigated. Students learn why engineers need to know the different properties of propellants.

Students are introduced to our Sun as they explore its composition, what is happening inside it, its relationship to our planet (our energy source), and the ways engineers help us learn about it.

Students will make a proportional model of blood out of red gelatin, a plastic bag, and rice. They will learn about the different components that make up blood and will investigate what happens when the arteries and veins experience buildup from cholesterol. They will then work in pairs to brainstorm ways to clean our clogged arteries.

Students are introduced to the circulatory system with an emphasis on the blood clotting process, including coagulation and the formation and degradation of polymers through their underlying atomic properties. They learn about the medical emergency of strokes the loss of brain function commonly due to blood clots including various causes and the different effects depending on the brain location, as well as blood clot removal devices designed by biomedical engineers.

Students study how heart valves work and investigate how valves that become faulty over time can be replaced with advancements in engineering and technology. Learning about the flow of blood through the heart, students are able to fully understand how and why the heart is such a powerful organ in our bodies.

Students make a skydiver and parachute contraption to demonstrate how drag caused by air resistance slows the descent of skydivers as they travel back to Earth. Gravity pulls the skydiver toward the Earth, while the air trapped by the parachute provides an upward resisting force (drag) on the skydiver.

Students are introduced to the circulatory system, the heart, and blood flow in the human body. Through guided pre-reading, during-reading and post-reading activities, students learn about the circulatory system's parts, functions and disorders, as well as engineering medical solutions. By cultivating literacy practices as presented in this lesson, students can improve their scientific and technological literacy.

Students learn about various crystals, such as kidney stones, within the human body. They also learn about how crystals grow and ways to inhibit their growth. They also learn how researchers such as chemical engineers design drugs with the intent to inhibit crystal growth for medical treatment purposes and the factors they face when attempting to implement their designs. A day before presenting this lesson to students, conduct the associated activity, Rock Candy Your Body.

Students design and build devices to protect and accurately deliver dropped eggs. The devices and their contents represent care packages that must be safely delivered to people in a disaster area with no road access. Similar to engineering design teams, students design their devices using a number of requirements and constraints such as limited supplies and time. The activity emphasizes the change from potential energy to kinetic energy of the devices and their contents and the energy transfer that occurs on impact. Students enjoy this competitive challenge as they attain a deeper understanding of mechanical energy concepts.

Students use a tension-compression machine (or an alternative bone-breaking setup) to see how different bones fracture differently and with different amounts of force, depending on their body locations. Teams determine bone mass and volume, calculate bone density, and predict fracture force. Then they each test a small animal bone (chicken, turkey, cat) to failure, examining the break to analyze the fracture type. Groups conduct research about biomedical challenges, materials and repair methods, and design repair treatment plans specific to their bones and fracture types, presenting their design recommendations to the class.

In their reading from activity 1 of this unit, students should have discovered the term "logarithm." It is at this point that they begin their study of logarithms. Specifically, students examine the definition, history and relationship to exponents; they rewrite exponents as logarithms and vice versa, evaluating expressions, solving for a missing piece. Students then study the properties of logarithms (multiplication/addition, division/subtraction, exponents). They complete a set of practice problems to apply the skills they have learned (rewriting logarithms and exponents, evaluating expressions, solving/examining equations for a missing variable.) Then they complete a short quiz covering what they have studied thus far concerning logarithms (problems similar to the practice problems). They consider how what they have learned moves them closer to answering the unit's challenge question.

Students learn about the role engineers and engineering play in repairing severe bone fractures. They acquire knowledge about the design and development of implant rods, pins, plates, screws and bone grafts. They learn about materials science, biocompatibility and minimally-invasive surgery.