Students explore orbit transfers and, specifically, Hohmann transfers. They investigate the orbits of Earth and Mars by using cardboard and string. Students learn about the planets' orbits around the sun, and about a transfer orbit from one planet to the other. After the activity, students will know exactly what is meant by a delta-v maneuver!

Simple and compound machines are designed to make work easier. When we encounter a machine that does not fit this understanding, the so-called machine seems absurd. In this lesson, the cartoons of Rube Goldberg are introduced and engage the students in critical thinking about the way his inventions make a simple task even harder to complete. As the final lesson in the simple machines unit, the study of Rube Goldberg machines can help students evaluate the importance and usefulness of the many machines around them.

Students learn about various natural hazards and specific methods engineers use to prevent these hazards from becoming natural disasters. They study a hypothetical map of an area covered with natural hazards and decide where to place natural disaster prevention devices by applying their critical thinking skills and an understanding of the causes of natural disasters.

Student teams practice water quality analysis through turbidity measurement and coliform bacteria counts. They use information about water treatment processes to design prototype small-scale water treatment systems and test the influent (incoming) and effluent (outgoing) water to assess how well their prototypes produce safe water to prevent water-borne illnesses.

Students build scale models of objects of their choice. In class they measure the original object and pick a scale, deciding either to scale it up or scale it down. Then they create the models at home. Students give two presentations along the way, one after their calculations are done, and another after the models are completed. They learn how engineers use scale models in their designs of structures, products and systems. Two student worksheets as well as rubrics for project and presentation expectations and grading are provided.

Students gain an understanding of the layers of the Earth by designing and building clay models.

Students learn what a pendulum is and how it works in the context of amusement park rides. While exploring the physics of pendulums, they are also introduced to Newton's first law of motion about continuous motion and inertia.

Students embark on a scavenger hunt around the school looking for indoor air pollution and mapping source locations.

In this lesson, students learn about major landforms (e.g., mountains, rivers, plains, valleys, canyons and plateaus) and how they occur on the Earth's surface. They learn about the civil and geotechnical engineering applications of geology and landforms, including the design of transportation systems, mining, mapping and measuring natural hazards.

Students examine the existence of sound by listening to and seeing sound waves while conducting a set of simple activities as a class or in pairs at stations. Students describe sound in terms of its pitch, volume and frequency. They use this knowledge to discuss how engineers study sound waves to help people who cannot hear or talk.

Students learn about seismology by using a sample seismograph constructed out of common classroom materials. The seismograph creates a seismogram based on vibrations caused by moving a ruler. The students work in groups to represent an engineering firm that must analyze the seismograph for how it works and how to read the seismogram it creates.

This unit describes a general approach to guiding students to complete service-based engineering design projects, with specific examples provided in detail as associated activities. With your class, brainstorm ideas for engineering designs that benefit your community or a specific person in your community. Then, guided by the steps of the engineering design process, have students research to understand background science and math, meet their client to understand the problem, and create, test and improve prototype devices. Note that service-based projects often take more time to prepare, especially if you arrange for a real client. However, the authors notice that students of both genders and all ethnicities tend to respond with more enthusiasm and interest to altruistic projects.

The earliest explorers did not have computers or satellites to help them know their exact location. The most accurate tool developed was the sextant to determine latitude and longitude. In this activity, the sextant is introduced and discussed with the class. Students will learn how a sextant can be a reliable tool that is still being used by today's navigators and how computers can help assure accuracy when measuring angles. Also, this activity will show how computers can be used to understand equations even when knowing how to do the math is unknown.

Students are introduced to the concepts of graywater and water reuse within households. They calculate the amount of used water a family generates in one day and use a model of home plumbing to find out how much graywater is produced in homes every day. They graph their results and discuss energy efficiency implications. Students are then challenged to find ways to reduce water use within the home.

Students investigate the critical nature of foundations as they learn differences between shallow and deep foundations, including the concepts of bearing pressure and settlement. Using models representing a shallow foundation and a deep pile foundation, they test, see and feel the effects in a cardboard box test bed composed of layers of pebbles, soil and sand. They also make bearing pressure calculations and recommendations for which type of foundations to use in various engineering scenarios.

Students learn about the major factors that comprise the design and construction cost of a modern bridge. Before a bridge design is completed, engineers provide overall cost estimates for construction of the bridge. Students learn about the components that go into estimating the total cost, including expenses for site investigation, design, materials, equipment, labor and construction oversight, as well as the trade-off between a design and its cost.

Students apply the mechanical advantages and problem-solving capabilities of six types of simple machines (wedge, wheel and axle, lever, inclined plane, screw, pulley) as they discuss modern structures in the spirit of the engineers and builders of the great pyramids. While learning the steps of the engineering design process, students practice teamwork, creativity and problem solving.

In this activity, students are challenged to design a contraption using simple machines to move a circus elephant into a rail car. After students consider their audience and constraints, they work in groups to brainstorm ideas and select one concept to communicate to the class.

This lesson discusses how each component of a spacecraft is specifically designed so that a rover can land safely in six minutes. Also, students will learn how common, everyday materials and technology, like nylon, polyester and airbags, are used in space-age technology.

Students examine collisions between two skateboards with different masses to learn about conservation of momentum in collisions.