In this lesson the students will learn how the heart functions. Students will be introduced to the concept of action potential generation. The lesson will explain how action potential generation causes the electrical current that causes muscle contraction in the heart. Students will be introduced to the basic electrical signal generated by the heart; P, QRS, and T waves. The lesson will approach the heart from an engineering standpoint and encourage students to design ways to improve heart function. Students will also learn the basic steps of the engineering design process.

Through two lessons and their associated activities, students do the work of scientists by designing their own experiments to answer questions they generate. Through a simple activity involving surface tension, students learn what a hypothesis is—and isn't—and why generating a hypothesis is an important aspect of the scientific method. In the second activity, with bubble gum to capture their interest, students learn to design and conduct controlled experiments to answer their own questions about the amounts of sugar (or artificial sweetener) in bubble or chewing gum.

Students observe natural selection in action and investigate the underlying mechanism, including random mutation and differential fitness based on environmental characteristics. They do this through use of the free AVIDA-ED digital evolution software application.

Students are introduced to static equilibrium by learning how forces and torques are balanced in a well-designed engineering structure. A tower crane is presented as a simplified two-dimensional case. Using Popsicle sticks and hot glue, student teams design, build and test a simple tower crane model according to these principles, ending with a team competition.

Use this hands-on activity to demonstrate rotational inertia, rotational speed, angular momentum, and velocity. Students build at least two simple spinners to conduct experiments with different mass distributions and shapes, as they strive to design and build the spinner that spins the longest.

Students are introduced to superhydrophobic surfaces and the "lotus effect." Water spilled on a superhydrophobic surface does not wet the surface, but simply rolls off. Additionally, as water moves across the superhydrophobic surface, it picks up and carries away any foreign material, such as dust or dirt. Students learn how plants create and use superhydrophobic surfaces in nature and how engineers have created human-made products that mimic the properties of these natural surfaces. They also learn about the tendency of all superhydrophobic surfaces to develop water droplets that do not roll off the surface but become "pinned" under certain conditions, such as water droplets formed from condensation. They see how the introduction of mechanical energy can "unpin" these water droplets and restore the desirable properties of the superhydrophobic surface.

Surface tension accounts for many of the interesting properties we associate with water. By learning about surface tension and adhesive forces, students learn why liquid jets of water break into droplets rather than staying in a continuous stream. Through hands-on activities, students learn how the combination of adhesive forces and cohesive forces cause capillary motion. They study different effects of capillary motion and use capillary motion to measure surface tension. Students explore the phenomena of wetting and hydrophobic and hydrophilic surfaces and see how water's behavior changes when a surface is treated with different coatings. A lotus leaf is a natural example of a superhydrophobic surface, with its water-repellent, self-cleaning characteristics. Students examine the lotus effect on natural leaves and human-made superhydrophobic surfaces, and explore how the lotus leaf repels dewy water through vibration. See the Unit Overview section for details on each lesson in this unit.

Students are presented with the question: "Why does a liquid jet break up into droplets?" and introduced to its importance in inkjet printers. A discussion of cohesive forces and surface tension is included, as well as surface acting agents (surfactants) and their ability to weaken the surface tension of water. Students observe the effects of surface tension using common household materials. Finally, students return to the original question through a homework assignment that helps them relate surface tension and surface area to the creation of water droplets from a liquid jet.

Students extend their understanding of surface tension by exploring the real-world engineering problem of deciding what makes a "good" soap bubble. Student teams first measure this property, and then use this measurement to determine the best soap solution for making bubbles. They experiment with additives to their best soap and water "recipes" to increase the strength or longevity of the bubbles. In a math homework, students perform calculations that explain why soap bubbles form spheres.

In an activity that integrates science and art, students see, experience and harness the phenomenon of surface tension as they create beautiful works of art. Students conduct two experiments related to surface tension floating objects on the surface of water and creating original artwork using floating inks. They also learn historical and cultural information through an introduction to the ancient Japanese art form of suminagashi. They take the topic a step further by discussing how an understanding of surface tension can be applied to solve real-world engineering problems and create useful inventions.

Students learn about the basics of molecules and how they interact with each other. They learn about the idea of polar and non-polar molecules and how they act with other fluids and surfaces. Students acquire a conceptual understanding of surfactant molecules and how they work on a molecular level. They also learn of the importance of surfactants, such as soaps, and their use in everyday life. Through associated activities, students explore how surfactant molecules are able to bring together two substances that typically do not mix, such as oil and water. This lesson and its associated activities are easily scalable for grades 3-12.

This unit focuses on teaching students about the many aspects of biomedical engineering (BME). Students come to see that BME is a broad field that relies on concepts from many engineering disciplines. They also begin to understand some of the special considerations that must be made when dealing with the human body. Activities and class discussions encourage students to think as engineers to come up with their own solutions to some of medical challenges that have been solved throughout the history of BME. Class time iincludes brainstorming and presenting ideas to the class for discussion. Specific activities include examination of the material properties and functions of surgical instruments and prosthetics, a simulation of the training experience of a surgical resident, and an investigation of the properties of fluid flow in vascular tissue.

Students engineer and evolve digital organisms with the challenge to produce organisms with the highest fitness values in a particular environment. They do this through use of the free Avida-ED digital evolution software application. The resulting organisms compete against each other in the same environment and students learn the benefits of applying the principles of natural selection to solve engineering design problems.

Using a household fan, cardboard box and paper towels, student teams design and build their own evaporative cooler prototype devices. They learn about the process that cools water during the evaporation of water. They make calculations to determine a room's cooling load, and thus determine the swamp cooler size. This activity adds to students' understanding of the behind-the-scenes mechanical devices that condition and move air within homes and buildings for human health and comfort.

Playing the role of engineers in collaborations with the marketing and production teams in a chocolate factory, students design a container for a jumbo chocolate bar. The projects constraints mean the container has to be a regular trapezoidal prism. The design has to optimize the material used to construct the container; that is, students have to find the dimensions of the container with the maximum volume possible. After students come up with their design, teams present a final version of the product that includes creative branding and presentation. The problem-solving portion of this project requires students to find a mathematical process to express the multiple variables in the prism’s volume formula as a single variable cubic polynomial function. Students then use technology to determine the value for which this function has a maximum and, with this value, find the prism’s optimal dimensions.

Students examine the motion of pendulums and come to understand that the longer the string of the pendulum, the fewer the number of swings in a given time interval. They see that changing the weight on the pendulum does not have an effect on the period. They also observe that changing the angle of release of the pendulum has negligible effect upon the period.

This activity demonstrates how potential energy (PE) can be converted to kinetic energy (KE) and back again. Given a pendulum height, students calculate and predict how fast the pendulum will swing by understanding conservation of energy and using the equations for PE and KE. The equations are justified as students experimentally measure the speed of the pendulum and compare theory with reality.

This activity shows students the engineering importance of understanding the laws of mechanical energy. More specifically, it demonstrates how potential energy can be converted to kinetic energy and back again. Given a pendulum height, students calculate and predict how fast the pendulum will swing by using the equations for potential and kinetic energy. The equations will be justified as students experimentally measure the speed of the pendulum and compare theory with reality.

Students explore how pendulums work and why they are useful in everyday applications. In a hands-on activity, they experiment with string length, pendulum weight and angle of release. In an associated literacy activity, students explore the mechanical concept of rhythm, based on the principle of oscillation, in a broader biological and cultural context in dance and sports, poetry and other literary forms, and communication in general.

Roller coasters projects are frequently used in middle and high school physics classes to illustrate the principle of conservation of mechanical energy. Potential energy transforms to kinetic energy and vice versa, with gravity being the driving force during the entire process. Even though friction force is mentioned, it is rarely considered in the velocity calculations along the coasters’ paths. In this high school lesson, the friction force is considered in the process. Using basic calculus and the work-energy theorem for non-conservative forces, the friction along a curved path is quantified, and the cart’s velocity along this path is predicted. This activity and its associated lesson are designed for AP Calculus. Practice problems/answers, a PowerPoint® presentation and student notes are provided.