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.

Using their knowledge of the phases of matter, the scientific method, and polymers, student teams work as if they are chemical engineers to optimize the formula for slime. Hired by the fictional company, Slime Productions, students are challenged to modify the chemical composition of the basic formula for slime to maximize its "bounce factor."

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.

Student groups work with manipulatives—pencils and trays—to maximize various quantities of a system. They work through three linear optimization problems, each with different constraints. After arriving at a solution, they construct mathematical arguments for why their solutions are the best ones before attempting to maximize a different quantity. To conclude, students think of real-world and engineering space optimization examples—a frequently encountered situation in which the limitation is the amount of space available. It is suggested that students conduct this activity before the associated lesson, Linear Programming, although either order is acceptable.

Students learn about how a device made with dye from a plant, specifically cherries, blackberries, raspberries and/or black currents, can be used to convert light energy into electrical energy. They do this by building their own organic solar cells and measuring the photovoltaic devices' performance based on power output.

For students that have already been introduced to the water cycle this lesson is intended as a logical follow-up. Students will learn about human impacts on the water cycle that create a pathway for pollutants beginning with urban development and joining the natural water cycle as surface runoff. The extent of surface runoff in an area depends on the permeability of the materials in the ground. Permeability is the degree to which water or other liquids are able to flow through a material. Different substances such as soil, gravel, sand, and asphalt have varying levels of permeability. In this lesson, along with the associated activities, students will learn about permeability and compare the permeability of several different materials for the purpose of engineering landscape drainage systems.

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.

Students are introduced to the fabulous planet on which they live. Even though we spend our entire lives on Earth, we still do not always understand how it fits into the rest of the solar system. Students learn about the Earth's position in the solar system and what makes it unique. They learn how engineers study human interactions with the Earth and design technologies and systems to monitor, use and care for our planet's resources wisely to preserve life on Earth.

Students learn about the human body's system components, specifically its sensory systems, nervous system and brain, while comparing them to robot system components, such as sensors and computers. The unit's life sciences-to-engineering comparison is accomplished through three lessons and five activities. The important framework of "stimulus-sensor-coordinator-effector-response" is introduced to show how it improves our understanding the cause-effect relationships of both systems. This framework reinforces the theme of the human body as a system from the perspective of an engineer. This unit is the second of a series, intended to follow the Humans Are Like Robots unit.

Students explore the outermost planets of our solar system: Saturn, Uranus and Neptune. They also learn about characteristics of Pluto and its interactions with Neptune. Students learn a little about the history of space travel as well as the different technologies that engineers develop to make space travel and scientific discovery possible.

Student groups are challenged to create food packages for specific foods. They focus on three components in the design of their food packages; the packages must keep the food clean, protect or aid in the physical and chemical changes that can take place in the food, and present the food appealingly. They design their packaging to meet these requirements.

Vision is the primary sense of many animals and much is known about how vision is processed in the mammalian nervous system. One distinct property of the primary visual cortex is a highly organized pattern of sensitivity to location and orientation of objects in the visual field. But how did we learn this? An important tool is the ability to design experiments to map out the structure and response of a system such as vision. In this activity, students learn about the visual system and then conduct a model experiment to map the visual field response of a Panoptes robot. (In Greek mythology, Argus Panoptes was the "all-seeing" watchman giant with 100 eyes.) A simple activity modification enables a true black box experiment, in which students do not directly observe how the visual system is configured, and must match the input to the output in order to reconstruct the unseen system inside the box.

Using paper, paper clips and tape, student teams design flying/falling devices to stay in the air as long as possible and land as close as possible to a given target. Student teams use the steps of the engineering design process to guide them through the initial conception, evaluation, testing and re-design stages. The activity culminates with a classroom competition and scoring to evaluate how each team's design performed.

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 engage in an interactive "hot potato" demonstration to gain an appreciation for the flow of electrons through a circuit. Students role play the different parts of a simple circuit and send small items representing electrons (paper or candy pieces) through the circuit.

In this activity, students will learn how water can be polluted by algal blooms. They will grow algae with different concentrations of fertilizer or nutrients and analyze their results as environmental engineers working to protect a local water resource.

Students investigate the property dependence between liquid and solid interfaces and determine observable differences in how liquids react to different solid surfaces. They compare copper pennies and plastic "coins" as the two test surfaces. Using an eye dropper to deliver various fluids onto the surfaces, students determine the volume and mass of a liquid that can sit on the surface. They use rulers, scales, equations of volume and area, and other methods of approximation and observation, to make their own graphical interpretations of trends. They apply what they learned to design two super-surfaces (from provided surface treatment materials) that arecapable of holding the most liquid by volume and by mass. Cost of materials is a parameter in their design decisions.

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.