Students expand upon their understanding of simple machines with an introduction to compound machines. A compound machine a combination of two or more simple machines can affect work more than its individual components. Engineers who design compound machines aim to benefit society by lessening the amount of work that people exert for even common household tasks. This lesson encourages students to critically think about machine inventions and their role in our lives.

This lesson will allow students to explore an important role of environmental engineers: cleaning the environment. Students will learn details about the Exxon Valdez oil spill, which was one of the most publicized and studied environmental tragedies in history. In the accompanying activity, they will try many "engineered" strategies to clean up their own manufactured oil spill and learn the difficulties of dealing with oil released into our waters.

This hands-on experiment will provide students with an understanding of the issues that surround environmental cleanup. Students will create their own oil spill, try different methods for cleaning it up, and then discuss the merits of each method in terms of effectiveness (cleanliness) and cost. They will be asked to put themselves in the place of both an environmental engineer and an oil company owner who are responsible for the clean-up.

Students learn about oil spills and their environmental and economic effects. They experience the steps of the engineering design process as they brainstorm potential methods for oil spill clean-up, and then design, build, and re-design oil booms to prevent the spread of oil spills. During a reflective session after cleaning up their oil booms, students come up with ideas on how to reduce oil consumption to prevent future oil spills.

The lesson begins by introducing Olympics as the unit theme. The purpose of this lesson is to introduce students to the techniques of engineering problem solving. Specific techniques covered in the lesson include brainstorming and the engineering design process. The importance of thinking out of the box is also stressed to show that while some tasks seem impossible, they can be done. This introduction includes a discussion of the engineering required to build grand, often complex, Olympic event centers.

In this activity, students learn about ocean currents and the difference between salt and fresh water. They use colored ice cubes to see how cold and warm water mix and how this mixing causes currents. Also, students learn how surface currents occur due to wind streams. Lastly, they learn how fresh water floats on top of salt water, the difference between water in the ocean and fresh water throughout the planet, and how engineers are involved in the design of ocean water systems for human use.

Looking at models and maps, students explore different pathways and consequences of pollutant transport via the weather and water cycles. In an associated literacy activity, students develop skills of observation, recording and reporting as they follow the weather forecast and produce their own weather report for the class.

Students work in engineering teams to optimize cleaner energy solutions for cooking and heating in rural China. They choose between various options for heating, cooking, hot water, and lights and other electricity, balancing between the cost and health effects of different energy choices.

The purpose of this lesson is to introduce the students to the Sun. They explore various aspects of the Sun including its composition, its interior workings, and its relationship to the Earth.

This lesson covers the topic of human bones and joints. Students learn about the skeleton, the number of and types of bones in the body, and how outer space affects astronauts' bones. Students also learn how to take care of their bones here on Earth to prevent osteoporosis or weakening of the bones.

This lesson goes over the parts of the human respiratory system and the gas exchange process that occurs in the lungs. It also covers changes in the respiratory system that occur during spaceflight, such as decreased lung capacity.

The difference between an architect and an engineer is sometimes confusing because their roles in building design can be similar. Students experience a bit of both professions by following a set of requirements and meeting given constraints as they create a model parking garage. They experience the engineering design process first-hand as they design, build and test their models. They draw a blueprint for their design, select the construction materials and budget their expenditures. They also test their structures for strength and find their maximum loads.

Students investigate how different riparian ground covers, such as grass or pavement, affect river flooding. They learn about permeable and impermeable materials through the measurement how much water is absorbed by several different household materials in a model river. Students use what they learn to make recommendations for engineers developing permeable pavement. Also, they consider several different limitations for design in the context of a small community.

This lesson covers the process of photosynthesis and the related plant cell functions of transpiration and cellular respiration. Students will learn how engineers can use the natural process of photosynthesis as an exemplary model of a complex yet efficient process for converting solar energy to chemical energy or distributing water throughout a system.

In this activity, students will learn about Newton's 2nd Law of Motion. They will learn that the force required to move a book is proportional to the weight of the book. Engineers use this relationship to determine how much force they need to move an airplane.

In this lesson, students learn that light travels in a straight line from a light source and that ray diagrams help us understand how an image will be created by a lens. In the accompanying activity, students explore the concepts behind the workings of a pinhole camera.

In this lesson, students learn about echolocation: what it is and how engineers use it to "see" things in the dark, or deep underwater. Also, they learn how animals use echolocation to catch their dinner and travel the ocean waters and skies without running into things.

To develop an understanding of modern industrial technologies that clean up and prevent air pollution, students build and observe a variety of simple models of engineering pollutant recovery methods: scrubber, electrostatic precipitator, cyclone and baghouse. In an associated literacy activity, students become more aware of global environmental problems and play a part in their solution by writing environmental action campaign letters.

Students design and build paper rockets around film canisters, which serve as engines. An antacid tablet and water are put into each canister, reacting to form carbon dioxide gas, and acting as the pop rocket's propellant. With the lid snapped on, the continuous creation of gas causes pressure to build up until the lid pops off, sending the rocket into the air. The pop rockets demonstrate Newton's third law of motion: for every action, there is an equal and opposite reaction.

Students use potatoes to light an LED clock (or light bulb) as they learn how a battery works in a simple circuit and how chemical energy changes to electrical energy. As they learn more about electrical energy, they better understand the concepts of voltage, current and resistance.