In this lesson, students will explore the causes of water pollution and its effects on the environment through the use of models and scientific investigation. In the accompanying activities, they will investigate filtration and aeration processes as they are used for removing pollutants from water. Lastly, they will learn about the role of engineers in water treatment systems.

Students analyze and begin to design a pyramid. Working in engineering teams, they perform calculations to determine the area of the pyramid base, stone block volumes, and the number of blocks required for their pyramid base. They make a scaled drawing of the pyramid using graph paper.

To navigate, you must know roughly where you stand relative to your designation, so you can head in the right direction. In locations where landmarks are not available to help navigate (in deserts, on seas), objects in the sky are the only reference points. While celestial objects move fairly predictably, and rough longitude is not too difficult to find, it is not a simple matter to determine latitude and precise positions. In this activity, students investigate the uses and advantages of modern GPS for navigation.

This hands-on activity explores the concept of static electricity. Students attract an O-shaped piece of cereal to a charged comb and watch the cereal jump away when it touches the comb. Students also observe Styrofoam pellets pulling towards a charged comb, then leaping back to the table.

Student groups rotate through four stations to examine light energy behavior: refraction, magnification, prisms and polarization. They see how a beam of light is refracted (bent) through various transparent mediums. While learning how a magnifying glass works, students see how the orientation of an image changes with the distance of the lens from its focal point. They also discover how a prism works by refracting light and making rainbows. And, students investigate the polar nature of light using sunglasses and polarized light film.

Students learn that math is important in navigation and engineering. They learn about triangles and how they can help determine distances. Ancient land and sea navigators started with the most basic of navigation equations (speed x time = distance). Today, navigational satellites use equations that take into account the relative effects of space and time. However, even these high-tech wonders cannot be built without pure and simple math concepts — basic geometry and trigonometry — that have been used for thousands of years.

Students learn about the strength of bones and methods of helping to mend fractured bones. During a class demonstration, a chicken bone is broken by applying a load until it reaches a point of failure (fracture). Then, working as biomedical engineers, students teams design their own splint or cast to help repair a fractured bone, learning about the strength of materials used.

In this activity, students act as engineers to determine which type of insulation would conserve the most energy.

Students learn that wind and storms can form at the boundaries of interacting high and low pressure air masses. They learn the distinguishing features of the four main types of weather fronts (warm fronts, cold fronts, stationary fronts and occluded fronts) and how those fronts are depicted on a surface weather analysis, or weather map. Students also learn several different ways that engineers help with storm prediction, analysis and protection.

Working as engineering teams, students design and create model beam bridges using plastic drinking straws and tape as their construction materials. Their goal is to build the strongest bridge with a truss pattern of their own design, while meeting the design criteria and constraints. They experiment with different geometric shapes and determine how shapes affect the strength of materials. Let the competition begin!

In this activity, students investigate the effect that fins have on rocket flight. Students construct two paper rockets that they can launch themselves by blowing through a straw. One "strawket" has wings and the other has fins. Students observe how these two control surfaces affect the flight of their strawkets. Students discover how difficult control of rocket flight is and what factors can affect it.

In this activity, students investigate the effect that thrust has on rocket flight. Students will make two paper rockets that they can launch themselves by blowing through a straw. These "strawkets" will differ in diameter, such that students will understand that a rocket with a smaller exit nozzle will provide a larger thrust. Students have the opportunity to compare the distances traveled by their two strawkets after predicting where they will land. Since each student will have a slightly different rocket and launching technique, they will observe which factors contribute to a strawket's thrust and performance.

In this activity, students investigate the effect that weight has on rocket flight. Students construct a variety of their own straw-launched rockets, or "strawkets," that have different weights. Specifically, they observe what happens when the weight of a strawket is altered by reducing its physical size and using different construction materials. Finally, the importance of weight distribution in a rocket is determined.

During this activity, students will learn how environmental engineers monitor water quality in resource use and design. They will employ environmental indicators to assess the water quality of a nearby stream. Students will make general observations of water quality as well as count the number of macroinvertabrates. They will then use the information they collected to create a scale to rate how good or bad the water quality of the stream. Finally, the class will compare their numbers and discuss and defend their results.

Students learn about the variety of materials used by engineers in the design and construction of modern bridges. They also find out about the material properties important to bridge construction and consider the advantages and disadvantages of steel and concrete as common bridge-building materials to handle compressive and tensile forces.

Students explore the physical and psychological effect of stress and tension on human beings. Concepts of stress and stress management are introduced. Students discover how perception serves to fuel a huge industry dedicated to minimizing risk and relieving stress. Students complete a writing activity focused on developing critical thinking skills. Note: The literacy activities for the Mechanics unit are based on physical themes that have broad application to our experience in the world concepts of rhythm, balance, spin, gravity, levity, inertia, momentum, friction, stress and tension.

Students are introduced to the concepts of stress and strain with examples that illustrate the characteristics and importance of these forces in our everyday lives. They explore the factors that affect stress, why engineers need to know about it, and the ways engineers describe the strength of materials. In an associated literacy activity, while learning about the stages of group formation, group dynamics and team member roles, students discover how collective action can alleviate personal feelings of stress and tension.

Students investigate how sound travels through string and air. First, they analyze the sound waves with a paper cup attached to a string. Then, they combine the string and cup with a partner to model a string telephone. Finally, they are given a design challenge to redesign the string telephone for distance. They think about their model as it compares a modern telephone and the impact the invention of the telephone has had on society.

Students generally do not know the complexity that goes into building and programming a robotic arm. In actuality, creating such an arm comes from a design that involves mechanical, electrical, and computer science engineers. This activity allows students to control a robotic arm from both a machine's and a computer science engineer's perspective by letting them perform a simple task with a few entertaining instructions and constraints.

To introduce the two types of stress that materials undergo compression and tension students examine compressive and tensile forces and learn about bridges and skyscrapers. They construct their own building structure using marshmallows and spaghetti to see which structure can hold the most weight. In an associated literacy activity, students explore the psychological concepts of stress and stress management, and complete a writing activity.