How must the environmental and engineering factors of designing a bridge be combined to create a safe bridge? People have built bridges over rivers, canyons, and other barriers for centuries. As engineers developed better technology and materials, the bridges became larger and stronger. Regardless of the type, all bridges apply common science principles related to forces, including tension and compression. Bridges of the future must be designed with lightweight materials that can withstand extreme weather events. Engineers must design bridges to create safe pathways for multiple forms of transportation, including bike lanes, pedestrian walkways, and passage for large cargo ships. Bridges can also be a source of inspiration, community gathering, and pride in a place. Bridges of the future must be designed with the community and environment in mind. Students will consider design criteria and constraints when defining an engineering problem. While analyzing the phenomena of the Hassanabad bridge collapse, students will consider the environmental and social factors involved in developing a structurally sound future bridge.

This is a 3-hour lesson that includes a self-paced interactive module and classroom activities. The teacher guide includes a challenge sequence (timeline), relevance to standards, materials list, print-outs, assessment, evaluation rubric, and learning extensions.

Lesson objectives: (1) Define and analyze the structural elements of bridges, including beams, arches, trusses, and suspension. (2) Identify tension and compression (tensile and compressive) forces in different types of bridges. (3) Analyze variables (materials, shapes used in the design, environmental factors) engineers must consider when designing a bridge with structural integrity with the ability to withstand a load (weather, cars, people, etc.)

Students work in groups to create soap bubbles on a smooth surface, recording their observations from which they formulate theories to explain what they see (color swirls on the bubble surfaces caused by refraction). Then they apply this theory to thin films in general, including porous films used in biosensors, listing factors that could change the color(s) that become visible to the naked eye, and learn how those factors can be manipulated to give information on gene detection. Finally (by experimentation or video), students see what happens when water is dropped onto the surface of a Bragg mirror.

SSAC Physical Volcanology module. Students build a spreadsheet and apply the ideal gas law to model the velocity of a bubble rising in a viscous magma.

Whether you want to light up a front step or a bathroom, it helps to have a light come on automatically when darkness falls. For this maker challenge, students create their own night-lights using Arduino microcontrollers, photocells and (supplied) code to sense light levels and turn on/off LEDs as they specify. As they build, test, and control these night-lights, they learn about voltage divider circuits and then experience the fundamental power of microcontrollers—controlling outputs (LEDs) based on sensor (photocell) input readings and if/then/else commands. Then they are challenged to personalize (and complicate) their night-lights—such as by using delays to change the LED blinking rate to reflect the amount of ambient light, or use many LEDs and several if/else statements with ranges to create a light meter. The possibilities are unlimited!

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.

Construct and measure the energy efficiency and solar heat gain of a cardboard model house. Use a light bulb heater to imitate a real furnace and a temperature sensor to monitor and regulate the internal temperature of the house. Use a bright bulb in a gooseneck lamp to model sunlight at different times of the year, and test the effectiveness of windows for passive solar heating.

Students are challenged to design their own small-sized prototype light sculptures to light up a hypothetical courtyard. To accomplish this, they use Arduino microcontrollers as the “brains” of the projects and control light displays composed of numerous (3+) light-emitting diodes (LEDs). With this challenge, students further their learning of Arduino fundamentals by exploring one important microcontroller capability—the control of external circuits. The Arduino microcontroller is a powerful yet easy-to-learn platform for learning computer programing and electronics. LEDs provide immediate visual success/failure feedback, and the unlimited variety of possible results are dazzling!

This classroom activity where students physically show where the forces are in an arch.

Students build their own small-scale model roller coasters using pipe insulation and marbles, and then analyze them using physics principles learned in the associated lesson. They examine conversions between kinetic and potential energy and frictional effects to design roller coasters that are completely driven by gravity. A class competition using different marbles types to represent different passenger loads determines the most innovative and successful roller coasters.

In this video segment adapted from ZOOM, the cast shows how the 34 steps in their Rube Goldberg invention use everything from gravity to carbon dioxide gas in order to accomplish one simple task: pouring a glass of milk.

In this video segment from ZOOM, Jillian explains how her simple machine uses marbles, levers, flowing sand, and a spinning wheel to water a plant.

To better understand the role of mass and gravity in the formation and existence of black holes we will model the collapse of a star into a black hole using aluminum foil. Along the way students will measure the decreasing circumference, and constant mass of their star as it collapses.

Estimated time required: 1-2 class periods.

Technology required for this lesson: .

A bungee jump involves jumping from a tall structure while connected to a large elastic cord. Design a bungee jump that is "safe" for a hard-boiled egg. Create a safety egg harness and connect it to a rubber band, which is your the "bungee cord." Finally, attach your bungee cord to a force sensor to measures the forces that push or pull your egg.

Students create and decorate their own spectrographs using simple materials and holographic diffraction gratings. A holographic diffraction grating acts like a prism, showing the visual components of light. After building the spectrographs, students observe the spectra of different light sources as homework.

A zip line is a way to glide from one point to another while hanging from a cable. Design and create a zip line that is safe for a hard-boiled egg. After designing a safety egg harness, connect the harness to fishing line or wire connected between two chairs of different heights using a paper clip. Learn to improve your zip line based on data. Attach a motion sensor at the bottom of your zip line and display a graph to show how smooth a ride your egg had!

Students construct electromagnets and determine that the more winds of wire coil around the core will increase the strength of the electromagnet.

How do you build a tunnel 32 miles long -- under water? This video segment adapted from Building Big, follows the construction of the Channel Tunnel (nicknamed "Chunnel"), the engineering wonder that connects England to France.

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.

This activity is a guided discovery where students gather information on how to add a seat belt to a clay figure that is sitting on top of a toy car. The clay figure should stay in place when it hits a speed bump placed after a ramp.

Students conduct a simple experiment to see how the water level changes in a beaker when a lump of clay sinks in the water and when the same lump of clay is shaped into a bowl that floats in the water. They notice that the floating clay displaces more water than the sinking clay does, perhaps a surprising result. Then they determine the mass of water that is displaced when the clay floats in the water. A comparison of this mass to the mass of the clay itself reveals that they are approximately the same.