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 learn about contact stress and its applications in engineering. They are introduced to the concept of heavy loads, such as buildings, elephants, people and traffic, and learn how those heavy loads apply contact stress. Through the analysis of their own footprints, students determine their contact stress.

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.

In this lesson the students will learn how the heart functions. Students will be introduced to the concept of action potential generation. The lesson will explain how action potential generation causes the electrical current that causes muscle contraction in the heart. Students will be introduced to the basic electrical signal generated by the heart; P, QRS, and T waves. The lesson will approach the heart from an engineering standpoint and encourage students to design ways to improve heart function. Students will also learn the basic steps of the engineering design process.

Students work together in small groups, while competing with other teams, to explore the engineering design process through a tower building challenge. They are given a set of design constraints and then conduct online research to learn basic tower-building concepts. During a two-day process and using only tape and plastic drinking straws, teams design and build the strongest possible structure. They refine their designs, incorporating information learned from testing and competing teams, to create stronger straw towers using fewer resources (fewer straws). They calculate strength-to-weight ratios to determine the winning design.

Music and sound are two different concepts that share much in common. Determining the difference between the two can sometimes be difficult due to the subjective nature of deciding what is or is not music. The goal of this activity is to take something constructed by students, that would be normally classified as just sound and have the class work together to make what can be perceived to be music. Students construct basic stringed instruments made of shoeboxes and rubber bands. This activity aims to increase student understanding of what distinguishes music from sound.

Through two lessons and their associated activities, students do the work of scientists by designing their own experiments to answer questions they generate. Through a simple activity involving surface tension, students learn what a hypothesis is—and isn't—and why generating a hypothesis is an important aspect of the scientific method. In the second activity, with bubble gum to capture their interest, students learn to design and conduct controlled experiments to answer their own questions about the amounts of sugar (or artificial sweetener) in bubble or chewing gum.

Students observe natural selection in action and investigate the underlying mechanism, including random mutation and differential fitness based on environmental characteristics. They do this through use of the free AVIDA-ED digital evolution software application.

Students culture cells in order to find out which type of surfactant (in this case, soap) is best at removing bacteria. Groups culture cells from unwashed hands and add regular bar soap, regular liquid soap, anti-bacterial soap, dishwasher soap, and hand sanitizer to the cultures. The cultures are allowed to grow for two days and then the students assess which type of soap design did the best job of removing bacteria cells from unwashed hands. Students extend their knowledge of engineering and surfactants for different environmental applications.

In this activity, students act as environmental engineers involved with the clean up of a toxic spill. Using bioremediation as the process, students select which bacteria they will use to eat up the pollutant spilled. Students learn how engineers use bioremediation to make organism degrade harmful chemicals. Engineers must make sure bacteria have everything they need to live and degrade contaminants for bioremediation to happen. Students learn about the needs of living things by setting up an experiment with yeast. The scientific method is reinforced as students must design the experiment themselves making sure they include a control and complete parts of a formal lab report.

Students learn about providing healthcare in a global setting and the importance of wearing protective equipment when treating patients with infectious diseases like Ebola. They learn about biohazard suits, heat transfer through conduction and convection and the engineering design cycle. Student teams design, create and test (and improve) their own Ebola biohazard suit prototypes that cover one arm and hand, including a ventilation system to cool the inside of the suit.

Students are introduced to static equilibrium by learning how forces and torques are balanced in a well-designed engineering structure. A tower crane is presented as a simplified two-dimensional case. Using Popsicle sticks and hot glue, student teams design, build and test a simple tower crane model according to these principles, ending with a team competition.

Students apply their knowledge of constructing and programming LEGO MINDSTORMS (TM)NXT robots to create sumobots - strong robots capable of pushing other robots out of a ring. To meet the challenge, groups follow the steps of the engineering design process and consider robot structure, weight and gear ratios in their designs to make their robots push as hard as possible to force robot opponents out of the ring. A class competition serves as the final test to determine the best designed robot, illustrating the interrelationships between designing, building and programming. This activity gives students the opportunity to be creative as well as have fun applying and combining what they have learned through the previous activities and lessons in this and prior units in the series. A PowerPoint (tm) presentation, pre/post quizzes and a worksheet are provided.