In the everyday electrical devices we use calculators, remote controls and cell phones a voltage source such as a battery is required to close the circuit and operate the device. In this hands-on activity, students use batteries, wires, small light bulbs and light bulb holders to learn the difference between an open circuit and a closed circuit, and understand that electric current only occurs in a closed circuit.

Students explore the concept of biodegradability by building and observing model landfills to test the decomposition of samples of everyday garbage items. They collect and record experiment observations over five days, seeing for themselves what happens to trash when it is thrown "away" in a landfill environment. This shows them the difference between biodegradable and non-biodegradable and serves to introduce them to the idea of composting. Students also learn about the role of engineering in solid waste management.

Accuracy of measurement in navigation depends very much on the situation. If a sailor's target is an island 200 km wide, sailing off center by 10 or 20 km is not a major problem. But, if the island were only 1 km wide, it would be missed if off just the smallest bit. Many of the measurements made while navigating involve angles, and a small error in the angle can translate to a much larger error in position when traveling long distances.

Students design, build and test reflectors to measure the effect of solar reflectance on the efficiency of solar PV panels. They use a small PV panel, a multimeter, cardboard and foil to build and test their reflectors in preparation for a class competition. Then they graph and discuss their results with the class. Complete this activity as part of the Photovoltaic Efficiency unit and in conjunction with the Concentrated Solar Power lesson.

Students make a simple conductivity tester using a battery and light bulb. They learn the difference between conductors and insulators of electrical energy as they test a variety of materials for their ability to conduct electricity.

Students learn about using renewable energy from the Sun for heating and cooking as they build and compare the performance of four solar cooker designs. They explore the concepts of insulation, reflection, absorption, conduction and convection.

Students learn the meaning of preservation and conservation and identify themselves and others as preservationists or conservationists in relation to specific environmental issues. They use Venn diagrams to clarify the similarities and differences in viewpoints. They see how an environmental point-of-view affects the approach to an engineering problem.

Students write poems using rhyme and meter as they come to understand the mechanical concept of rhythm, based on the principle of oscillation, in a broader biological and cultural context, as seen in dance and sports, poetry and other literary forms, and communication in general. 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 learn about the many types of expenses associated with building a bridge. Working like engineers, they estimate the cost for materials for a bridge member of varying sizes. After making calculations, they graph their results to compare how costs change depending on the use of different materials (steel vs. concrete). They conclude by creating a proposal for a city bridge design based on their findings.

Students design a simple behavioral survey, and learn basic protocol for primary research, survey design and report writing. 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.

The students discover the basics of heat transfer in this activity by constructing a constant pressure calorimeter to determine the heat of solution of potassium chloride in water. They first predict the amount of heat consumed by the reaction using analytical techniques. Then they calculate the specific heat of water using tabulated data, and use this information to predict the temperature change. Next, the students will design and build a calorimeter and then determine its specific heat. After determining the predicted heat lost to the device, students will test the heat of solution. The heat given off by the reaction can be calculated from the change in temperature of the water using an equation of heat transfer. They will compare this with the value they predicted with their calculations, and then finish by discussing the error and its sources, and identifying how to improve their design to minimize these errors.

Students learn about the physical force of linear momentum movement in a straight line by investigating collisions. They learn an equation that engineers use to describe momentum. Students also investigate the psychological phenomenon of momentum; they see 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.

Student teams investigate the properties of electromagnets. They create their own small electromagnet and experiment with ways to change its strength to pick up more paper clips. Students learn about ways that engineers use electromagnets in everyday applications.

Students pretend they are agricultural engineers during the colonial period and design a miniature plow that cuts through a "field" of soil. They are introduced to the engineering design process and learn of several famous historical figures who contributed to plow design.

Students reinforce their knowledge that DNA is the genetic material for all living things by modeling it using toothpicks and gumdrops that represent the four biochemicals (adenine, thiamine, guanine, and cytosine) that pair with each other in a specific pattern, making a double helix. They investigate specific DNA sequences that code for certain physical characteristics such as eye and hair color. Student teams trade DNA "strands" and de-code the genetic sequences to determine the physical characteristics (phenotype) displayed by the strands (genotype) from other groups. Students extend their knowledge to learn about DNA fingerprinting and recognizing DNA alterations that may result in genetic disorders.

As a class, students work through an example showing how DNA provides the "recipe" for making our body proteins. They see how the pattern of nucleotide bases (adenine, thymine, guanine, cytosine) forms the double helix ladder shape of DNA, and serves as the code for the steps required to make genes. They also learn some ways that engineers and scientists are applying their understanding of DNA in our world.

By tracing the movement of radiation released during an accident at the Chernobyl nuclear power plant, students see how air pollution, like particulate matter, can become a global issue.

Students explore the many different ways that engineers provide natural lighting to interior spaces. They analyze various methods of daylighting by constructing model houses from foam core board and simulating the sun with a desk lamp. Teams design a daylighting system for their model houses based on their observations and calculations of the optimal use of available sunlight to their structure.

Students explore the densities and viscosities of fluids as they create a colorful 'rainbow' using household liquids. While letting the fluids in the rainbow settle, students conduct 'The Great Viscosity Race,' another short experiment that illustrates the difference between viscosity and density. Later, students record the density rainbow with sketches and/or photography.

Students discover how engineers can use biomimicry to enhance their designs. They learn how careful observation of nature becoming a nature detective, so to speak can lead to new innovations and products. In this activity, students reverse engineer a flower to glean design ideas for new products.