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.

Students learn how the process of soil solarization is used to pasteurize agricultural fields before planting crops. Soil solarization is a pest control technique in agriculture that uses the sun’s radiation to heat the soil and eliminate unwanted pests that could harm the crops. The approach is compared to other pest control methods such as fumigation and herbicide application, highlighting the respective benefits and drawbacks. In preparation for the associated hands-on activity on soil biosolarization, students learn how changing the variables involved in the solarizing process (such as the tarp material, soil water content and addition of organic matter) impacts the technique’s effectiveness. A PowerPoint® presentation and pre/post-quiz is provided.

Students learn how the force of water helps determine the size and shape of dams. They use clay to build models of four types of dams, and observe the force of the water against each type. They conclude by deciding which type of dam they, as Splash Engineering engineers, will design for Thirsty County.

While the creation of a dam provides many benefits, it can have negative impacts on local ecosystems. Students learn about the major environmental impacts of dams and the engineering solutions used to address them.

Students conduct Internet research to investigate the purpose and current functioning status of some of the largest dams throughout the world. They investigate the success or failure of eight dams and complete a worksheet. While researching the dams, they also gain an understanding of the scale of these structures by recording and comparing their reservoir capacities. Students come to understand that dams, like all engineered structures, have a finite lifespan and require ongoing maintenance and evaluation for their usefulness.

Through eight lessons, students are introduced to many facets of dams, including their basic components, the common types (all designed to resist strong forces), their primary benefits (electricity generation, water supply, flood control, irrigation, recreation), and their importance (historically, currently and globally). Through an introduction to kinetic and potential energy, students come to understand how dams generate electricity. They learn about the structure, function and purpose of locks, which involves an introduction to Pascal's law, water pressure and gravity. Other lessons introduce students to common environmental impacts of dams and the engineering approaches to address them. They learn about the life cycle of salmon and the many engineered dam structures that aid in their river passage, as they think of their own methods and devices that could help fish migrate past dams. Students learn how dams and reservoirs become part of the Earth's hydrologic cycle, focusing on the role of evaporation. To conclude, students learn that dams do not last forever; they require ongoing maintenance, occasionally fail or succumb to "old age," or are no longer needed, and are sometimes removed. Through associated hands-on activities, students track their personal water usage; use clay and plastic containers to model and test four types of dam structures; use paper cups and water to learn about water pressure and Pascal's Law; explore kinetic energy by creating their own experimental waterwheel from two-liter plastic bottles; collect and count a stream's insects to gauge its health; play an animated PowerPoint game to quiz their understanding of the salmon life cycle and fish ladders; run a weeklong experiment to measure water evaporation and graph their data; and research eight dams to find out and compare their original purposes, current status, reservoir capacity and lifespan. Woven throughout the unit is a continuing hypothetical scenario in which students act as consulting engineers with a Splash Engineering firm, assisting Thirsty County in designing a dam for Birdseye River.

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 learn about and practice converting between fractions, decimals and percentages. Using a LEGO® MINDSTORMS® NXT robot and a touch sensor, each group inputs a fraction of its choosing. Team members convert this same fraction into a decimal, and then a percentage via hand calculations, and double check their work using the NXT robot. Then they observe the robot moving forward and record that distance. Students learn that the distance moved is a fraction of the full distance, based on the fraction that they input, so if they input ½, the robot moves half of the original distance. From this, students work backwards to compute the full distance. Groups then compete in a game in which they are challenged to move the robot as close as possible to a target distance by inputting a fraction into the NXT bot.

Students learn about nanocomposites, compression and strain as they design and program robots that compress materials. Student groups conduct experiments to determine how many LEGO MINDSTORMS(TM) NXT motor rotations it takes to compress soft nanocomposites, including mini marshmallows, Play-Doh®, bread and foam. They measure the length and width of their nanocomposite objects before and after compression to determine the change in length and width as a function of motor rotation.

In this first part of a two-part lab activity, students use triple balance beams and graduated cylinders to take measurements and calculate the densities of several common, irregularly shaped objects with the purpose to resolve confusion about mass and density. After this activity, conduct the associated Density Column Lab - Part 2 activity before presenting the associated Density & Miscibility lesson for discussion about concepts that explain what students have observed.

Concluding a two-part lab activity, students use triple balance beams and graduated cylinders to take measurements and calculate densities of several household liquids and compare them to the densities of irregularly shaped objects (as determined in Part 1). Then they create density columns with the three liquids and four solid items to test their calculations and predictions of the different densities. Once their density columns are complete, students determine the effect of adding detergent to the columns. After this activity, present the associated Density & Miscibility lesson for a discussion about why the column layers do not mix.

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 design and build model landfills using materials similar to those used by engineers for full-scale landfills. Their completed small-size landfills are "rained" on and subjected to other erosion processes. The goal is to create landfills that hold the most garbage, minimize the cost to build and keep trash and contaminated water inside the landfill to prevent it from causing environmental damage. Teams create designs within given budgets, test the landfills' performance, and graph and compare designs for capacity, cost and performance.

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.

Students use their creative skills to determine a way to safely mail raw (dry, uncooked) spaghetti using only the provided materials. To test the packing designs, the spaghetti is mailed through the postal system and evaluated after delivery.

Students practice the initial steps involved in an engineering design challenge. They begin by reviewing the steps of the engineering design loop and discussing the client need for the project. Next, they identify a relevant context, define the problem within their design teams, and examine the project's requirements and constraints. (Note: Conduct this activity in the context of a design project that students are working on, which could be a challenge determined by the teacher, brainstormed with the class, or the example project challenge provided [to design a prosthetic arm that can perform a mechanical function].)

Through Internet research, patent research, standards and codes research, user interviews (if possible) and other techniques (idea web, reverse engineering), students further develop the context for their design challenge. In subsequent activities, the design teams use this body of knowledge about the problem to generate product design ideas. (Note: Conduct this activity in the context of a design project that students are working on, which could be a challenge determined by the teacher, brainstormed with the class, or the example project challenge provided [to design a prosthetic arm that can perform a mechanical function]. This activity is Step 2 in a series of six that guide students through the engineering design loop.)

Brainstorming is a team creativity activity that helps generate a large number of potential solutions to a problem. In this activity, students participate in a group brainstorming activity to generate possible solutions to their engineering design challenge. Students learn brainstorming guidelines and practice within their teams to create a poster of ideas. The posters are used in a large group critiquing activity that ultimately helps student teams create a design project outline. (Note: Conduct this activity in the context of a design project that students are working on; this activity is Step 3 in a series of six that guide students through the engineering design loop.)

Engineering analysis distinguishes true engineering design from "tinkering." In this activity, students are guided through an example engineering analysis scenario for a scooter. Then they perform a similar analysis on the design solutions they brainstormed in the previous activity in this unit. At activity conclusion, students should be able to defend one most-promising possible solution to their design challenge. (Note: Conduct this activity in the context of a design project that students are working on; this activity is Step 4 in a series of six that guide students through the engineering design loop.)