Students culture cells in order to find out which type of surfactant (in this case, soap) is best at removing bacteria. Groups culture cells from unwashed hands and add regular bar soap, regular liquid soap, anti-bacterial soap, dishwasher soap, and hand sanitizer to the cultures. The cultures are allowed to grow for two days and then the students assess which type of soap design did the best job of removing bacteria cells from unwashed hands. Students extend their knowledge of engineering and surfactants for different environmental applications.

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 conduct an experiment to determine whether or not the sense of smell is important to being able to recognize foods by taste. They do this by attempting to identify several different foods that have similar textures. For some of the attempts, students hold their noses and close their eyes, while for others they only close their eyes. After they have conducted the experiment, they create bar graphs showing the number of correct and incorrect identifications for the two different experimental conditions tested.

Students are introduced to an engineering challenge in which they are given a job assignment to separate three types of apples. However, they are unable to see the color differences between the apples, and as a result, they must think as engineers to design devices that can be used to help them distinguish the apples from one another. Solving the challenge depends on an understanding of wave properties and the biology of sight. After being introduced to the challenge, students form ideas and brainstorm about what background knowledge is required to solve the challenge. A class discussion produces student ideas that can be grouped into broad subject categories: waves and wave properties, light and the electromagnetic spectrum, and the structure of the eye.

Towers have been a part of developed society for centuries, serving a variety of purposes, from watch towers to modern cell towers. In this activity, student groups design and build three types of towers (guyed or cable-supported, free-standing or self-standing, and monopole), engineering them to meet the requirements that they hold an egg one foot high for 15 seconds.

Students use the spectrograph from the "Building a Fancy Spectrograph" activity to gather data about different light sources. Using the data, they make comparisons between the light sources and make conjectures about the composition of these sources.

Students use inclined planes as they recreate the difficult task of raising a monolith of rock to build a pyramid. They compare the push and pull of different-sized blocks up an inclined plane, determine the angle of inclination, and learn the changes that happen when the angle is increased or decreased.

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 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.

Students learn about the definition of heat as a form of energy and how it exists in everyday life. They learn about the three types of heat transfer conduction, convection and radiation as well as the connection between heat and insulation. Their learning is aided by teacher-led class demonstrations on thermal energy and conduction. A PowerPoint® presentation and quiz are provided. This prepares students for the associated activity in which they experiment with and measure what they learned in the lesson by designing and testing insulated bottles.

Students are introduced to Newton's third law of motion: For every action, there is an equal and opposite reaction. They practice identifying action-reaction force pairs for a variety of real-world examples, and draw and explain simplified free-body diagram vectors (arrows) of force, velocity and acceleration for them. They also learn that engineers apply Newton's third law and an understanding of reaction forces when designing a wide range of creations, from rockets and aircraft to door knobs, rifles and medicine delivery systems. This lesson is the third in a series of three lessons intended to be taught prior to a culminating associated activity to complete the unit.

During this activity, students learn how oil is formed and where in the Earth we find it. Students take a core sample to look for oil in a model of the Earth. They analyze their sample and make an informed decision as to whether or not they should "drill for oil" in a specific location.

Students learn about physical models of groundwater and how environmental engineers determine possible sites for drinking water wells. During the activity, students create their own groundwater well models using coffee cans and wire screening. They add red food coloring to their models to see how pollutants can migrate through the groundwater into a drinking water resource.

Students act as food science engineers as they explore and apply their understanding of cooling rate and specific heat capacity by completing two separate, but interconnected, tasks. In Part 1, student groups conduct an experiment to explore the cooling rate of a cup of hot chocolate. They collect and graph data to create a mathematical model that represents the cooling rate, and use an exponential decay regression to determine how long a person should wait to drink the cup of hot chocolate at an optimal temperature. In Part 2, students investigate the specific heat capacity of the hot chocolate. They determine how much energy is needed to heat the hot chocolate to an optimal temperature after it has cooled to room temperature. Two activity-guiding worksheets are included.

Students build their own simple conductivity tester and explore whether given solid materials and solutions of liquids are good conductors of electricity.

Students learn about wind energy by making a pinwheel to model a wind turbine. Just like engineers, they decide where and how their turbine works best by testing it in different areas of the playground.

In this activity, students develop an understanding of how engineers use wind to generate electricity. They will build a model anemometer to better understand and measure wind speed.

Students learn about archives and primary sources as they research original historical documents. While preparing an imaginative first-person account as if witnessing an historical event, they learn to appreciate the value of the first-person, eye-witness account and understand its limitations. 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.