Students use a simple pH indicator to measure how much CO2 is produced during respiration, at rest and after exercising. They begin by comparing some common household solutions in order to determine the color change of the indicator. They review the concepts of pH and respiration and extend their knowledge to measuring the effectiveness of bioremediation in the environment.

Students explore how tension and compression forces act on three different bridge types. Using sponges, cardboard and string, they create models of beam, arch and suspension bridges and apply forces to understand how they disperse or transfer these loads.

Students are presented with a brief history of bridges as they learn about the three main bridge types: beam, arch and suspension. They are introduced to two natural forces tension and compression common to all bridges and structures. Throughout history, and today, bridges are important for connecting people to resources, places and other people. Students become more aware of the variety and value of bridges around us in our everyday lives.

In this hands-on activity, students explore the electrical force that takes place between two objects. Each student builds an electroscope and uses the device to draw conclusions about objects' charge intensity. Students also determine what factors influence electric force.

Working as if they are engineers who work for (the hypothetical) Build-a-Toy Workshop company, students apply their imaginations and the engineering design process to design and build prototype toys with moving parts. They set up electric circuits using batteries, wire and motors. They create plans for project material expenses to meet a budget.

Students create their own anemometers instruments for measuring wind speed. They see how an anemometer measures wind speed by taking measurements at various school locations. They also learn about different types of anemometers, real-world applications, and how wind speed information helps engineers decide where to place wind turbines.

Students learn about atoms and their structure (protons, electrons, neutrons) — the building blocks of matter. They see how scientific discoveries about atoms and molecules influence new technologies developed by engineers.

Students investigate the weather from a systems approach, learning how individual parts of a system work together to create a final product. Students learn how a barometer works to measure the Earth's air pressure by building a model using simple materials. Students analyze the changes in barometer measurements over time and compare those to actual weather conditions. They learn how to use a barometer to understand air pressure and predict actual weather changes.

Students use their knowledge of tornadoes and damage. The students will work in groups to design a structure that will withstand and protect people from tornadoes. Each group will create a poster with the name of their engineering firm and a picture of their structure. Finally, each group will present their posters to the class.

We are surrounded everyday by circuits that utilize "in parallel" and "in series" circuitry. Complicated circuits designed by engineers are made of many simpler parallel and series circuits. In this hands-on activity, students build parallel circuits, exploring how they function and their unique features.

Everyday we are surrounded by circuits that use "in parallel" and "in series" circuitry. Complicated circuits designed by engineers are composed of many simpler parallel and series circuits. During this activity, students build a simple series circuit and discover the properties associated with series circuits.

In this lesson, students learn that navigational techniques change when people travel to different places land, sea, air and in space. For example, an explorer traveling by land uses different methods of navigation than a sailor or an astronaut.

Students construct three-dimensional models of water catchment basins using everyday objects to form hills, mountains, valleys and water sources. They experiment to see where rain travels and collects, and survey water pathways to see how they can be altered by natural and human activities. Students discuss how engineers design structures that impact water collection, as well as systems that clean and distribute water.

This lesson introduces students to the concept of air pressure. Students will explore how air pressure creates force on an object. They will study the relationship between air pressure and the velocity of moving air.

In the exploration of ways to use solar energy, students investigate the thermal energy storage capacities of different test materials to determine which to use in passive solar building design.

Students are introduced to the concept of energy cycles by learning about the carbon cycle. They will learn how carbon atoms travel through the geological (ancient) carbon cycle and the biological/physical carbon cycle. Students will consider how human activities have disturbed the carbon cycle by emitting carbon dioxide into the atmosphere. They will discuss how engineers and scientists are working to reduce carbon dioxide emissions. Lastly, students will consider how they can help the world through simple energy conservation measures.

Students consider the Earth's major types of landforms such as mountains, rivers, plains, hills, canyons, oceans and plateaus. Student teams build three-dimensional models of landscapes, depicting several of these landforms. Once the models are built, they act as civil and transportation engineers to design and build roads through the landscapes they have created. The worksheet is provided in English and Spanish.

Working in teams of three, students perform quantitative observational experiments on the motion of LEGO MINDSTORMS(TM) NXT robotic vehicles powered by the stored potential energy of rubber bands. They experiment with different vehicle modifications (such as wheel type, payload, rubber band type and lubrication) and monitor the effects on vehicle performance. The main point of the activity, however, is for students to understand that through the manipulation of mechanics, a rubber band can be used in a rather non-traditional configuration to power a vehicle. In addition, this activity reinforces the idea that elastic energy can be stored as potential energy.

Students learn about power generation using river currents. A white paper is a focused analysis often used to describe how a technology solves a problem. In this literacy activity, students write a simplified version of a white paper on an alternative electrical power generation technology. In the process, they develop their critical thinking skills and become aware of the challenge and promise of technological innovation that engineers help to make possible. This activity is geared towards fifth grade and older students and computer capabilities are required. Some portions of the activity may be appropriate with younger students. CAPTION: Upper Left: Trey Taylor, President of Verdant Power, talks about green power with a New York City sixth-grade class. Lower Left: Verdant Power logo. Center: Verdant Power's turbine evaluation vessel in New York's East River. In the background is a conventional power plant. Upper Right: The propeller-like turbine can be raised and lowered from the platform of the turbine evaluation vessel. Lower Right: Near the East River, Mr. Taylor explains to the class how water currents can generate electric power.

Students observe the relationship between the angle of a catapult (a force measurement) and the flight of a cotton ball. They learn how Newton's second law of motion works by seeing directly that F = ma. When they pull the metal "arm" back further, thus applying a greater force to the cotton ball, it causes the cotton ball to travel faster and farther. Students also learn that objects of greater mass require more force to result in the same distance traveled by a lighter object.