Students learn how the total solar irradiance hitting a photovoltaic (PV) panel can be increased through the use of a concentrating device, such as a reflector or lens. This is the final lesson in the Photovoltaic Efficiency unit and is intended to accompany a fun design project (see the associated Concentrating on the Sun with PVs activity) to wrap up the unit. However, it can be completed independently of the other unit lessons and activities.

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.

Los estudiantes construyen un probador de conductividad y prueban una variedad de materiales para determinar si son buenos conductores de electricidad.

With the help of simple, teacher-led demonstration activities, students learn the basic concepts of heat transfer by means of conduction, convection, and radiation. Students then apply these concepts as they work in teams to solve two problems. One problem requires that they maintain the warm temperature of one soda can filled with water at approximately body temperature, and the other problem is to cause an identical soda can of warm water to cool as much as possible during the same thirty-minute time interval. Students design their solutions using only common, everyday materials. They record the water temperatures in their two soda cans every five minutes, and prepare line graphs in order to visually compare their results to the temperature of an unaltered control can of water.

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 isometric drawings and practice sketching on triangle-dot paper the shapes they make using multiple simple cubes. They also learn how to use coded plans to envision objects and draw them on triangle-dot paper. A PowerPoint® presentation, worksheet and triangle-dot (isometric) paper printout are provided. This activity is part of a multi-activity series towards improving spatial visualization skills.

Students are introduced to the idea of improving efficiency by examining a setting that is familiar to many teenagers fast food restaurants. More specifically, they learn about the concepts of trade-offs, constraints, increasing efficiency and systems thinking. They consider how to improve efficiency in a struggling restaurant through delegating tasks, restructuring employee responsibilities and revising a floor plan, all while working within limitations and requirements. Finally, students summarize and defend their suggested changes in argumentative essays.

Students use simple household materials, such as PVC piping and compact mirrors, to construct models of laser-based security systems. The protected object (a "mummified troll" or another treasure of your choosing) is placed "on display" in the center of the modeled room and protected by a laser system that utilizes a laser beam reflected off mirrors to trigger a light trip sensor with alarm.

We design and create objects to make our lives easier and more comfortable. The houses in which we live are excellent examples of this. Depending on your local climate, the features of your house have been designed to satisfy your particular environmental needs: protection from hot, cold, windy and/or rainy weather. In this activity, students design and build model houses, then test them against various climate elements, and then re-design and improve them. Using books, websites and photos, students learn about the different types of roofs found on various houses in different environments throughout the world.

Is the food chain shown above accurate? Does the first link depict a producer, the second link a herbivore, and the third link an omnivore / carnivore? Students must correctly determine whether a species is a producer or consumer, and what type of consumer; herbivore, omnivore, or carnivore. Students are provided with a list of Sonoran Desert species and asked to construct, within their groups, several food chains. These food chains are then be used to construct a food web. In order to complete this activity, students must first research the individual species to understand their feeding habits.

Students use the robot paths they documented during the associated Robots on Ice Engineering Challenge activity to learn about and then make artwork. During the previous activity, students recorded the path of their robots through a maze in order to collect data during a remote research simulation. Now, they take a new look at the robot paths, seeing them from an art perspective as continuous line drawings. Students learn about Picasso’s famous works of art that used the same technique. Then they learn the artistic definition of a line and see examples of how it is used in different art pieces; they practice making continuous line drawings and then create sculptures of their drawings using colorful wire. A PowerPoint® presentation is provided to guide the activity.

Students gain a deeper understanding of how sound sensors work through a hands-on design challenge involving LEGO MINDSTORMS(TM) NXT taskbots and sound sensors. Student groups each program a robot computer to use to the sound of hand claps to control the robot's movement. They learn programming skills and logic design in parallel. They experience how robots can take sensor input and use it to make decisions to move and turn, similar to the human sense of hearing. A PowerPoint® presentation and pre/post quizzes are provided.

Bluetooth is everywhere—from smartphones to computers to cars. Even though students are exposed to this technology, many are not aware of how they can use it themselves to wirelessly control their own creative projects! For this challenge, students build on what they learned during a previous Arduino maker challenge, Make and Control a Servo Arm with Your Computer, and learn how to control a servo with an Android phone (iPhones do not work with the components used in this challenge). By the end of the exercise, expect students to be wirelessly controlling a servo with a simple phone application!

In this activity, students use a variety of materials to design and create headphones that absorb sound.

Students teams design and build shoe prototypes that convert between high heels and athletic shoes. They apply their knowledge about the mechanics of walking and running as well as shoe design (as learned in the associated lesson) to design a multifunctional shoe that is both fashionable and functional.

Students act as mining engineers and simulate ore mining production by using chocolate chip cookies. They focus on the cost-benefit analysis of the chocolate ore production throughout the simulation, which helps them understand the cost of production. As students “mine” with tools such as paperclips and toothpicks, they keep records of their costs—land (cookie), equipment used, cookie size before and after production, and time spent. While the goal is to make as much profit as possible, other costs and goals are taken into consideration—as in real-world mining engineering. For example, mining engineers also consider the resulting amount of destruction to the lithosphere when deciding the best method to obtain ore. Thus, a line item for land reclamation cost is included from the beginning. A provided worksheet serves as a profit and loss statement.

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.

Student groups are given a set of materials: cardboard, insulating materials, aluminum foil and Plexiglas, and challenged to build solar ovens. The ovens must collect and store as much of the sun's energy as possible. Students experiment with heat transfer through conduction by how well the oven is insulated and radiation by how well it absorbs solar radiation. They test the effectiveness of their designs qualitatively by baking something and quantitatively by taking periodic temperature measurements and plotting temperature vs. time graphs. To conclude, students think like engineers and analyze the solar oven's strengths and weaknesses compared to conventional ovens.