Lesson Plan Index
To Build A Bridge

 To Build A Bridge - by Viki Babcock (middle/high school science) Students explore the different facets that must be considered to design and construct a bridge. They start with a look at materials vs. design and then end up with a brief look at some of the ethical concerns of engineering projects.
Estimated class time:

Two 90-minute blocks

Lesson Objectives:

Students will:
• Design and create simple model bridges
• Compare materials used in bridge construction
• Research basic bridge building design concepts
• Evaluate ethical impacts of building the bridge on the River Kwai
Materials needed:

• Internet access
• TV/VCR
• DVD player
• Copy of SECRETS OF THE DEAD IV: Bridge On The River Kwai
• For each pair of students: two paper cups, one strip of paper, and one strip of heavy duty aluminum foil (both approximately 10 cm by 28 cm) and 10 to 20 pennies or other coins
• Copies of handout
Teaching Strategy:

 Teachers! Video clips for your students are available here. Video Clips
1. Provide students with handout and ask them to predict which material would make a better bridge -- paper or metal. Then give them a chance to test their predictions.

2. Allow the students to work in pairs. Provide each pair of students with two small paper cups (or small 50 ml beakers will work as well), one strip of paper, one strip of aluminum foil, and 10 to 20 pennies. Challenge the students to use the provided materials to create a bridge strong enough to hold at least 5 pennies in the middle between the two paper cups.

3. If students need hints, tell them that the key is in how they fold the material they're using. Both bridges will work well if students make alternating pleat folds, as if they were making a paper fan. The pleated strip of paper or aluminum laid across the two supports will then be able to hold several coins.

4. Once all students have created successful bridges, have them determine which one is actually stronger -- aluminum or paper -- by continuing to add weight (pennies) until the bridge collapses. The paper will most likely hold more weight than the aluminum.

5. As a class, discuss the results of this activity. Things to consider include:

• What kinds of things did the students try to make their bridges work?

• Which designs were more successful?

• What seems to make a bigger difference in their bridges -- the material used or the actual design?

 Interactive Quiz Ride the Rails Ride the rails of the Thailand-Burma Railway in this fun quiz.
Conclude the discussion by having the pairs of students brainstorm a list of things that must be considered when building a bridge and record their lists on their handouts. Lead students, if necessary, to distance of span, types of materials available, type of load bridge will be supporting, geography of bridge location, costs, design, aesthetics, etc.

6. Direct students to the Clues and Evidence page of SECRETS OF THE DEAD's Bridge on the River Kwai at http://www.pbs.org/wnet/secrets/case_kwai/clues.html. After reading, discuss the pros and cons of building with wood. Also discuss what made the Thailand-Burma Railway such a remarkable feat.

7. Have students find out more about bridge building basics by researching on the Internet. Suggest some of the following links, if desired. Students can summarize what they learn on the handout. Students can find their own "Bridge Vocabulary" by listing and defining new terms they find in the Web sites. Or teachers can provide a list of terms to search for in the Web sites, such as span, buckling, dissipate, truss, beam, resonance, dampeners, etc.

8. Introduce the video SECRETS OF THE DEAD IV: Bridge On The River Kwai. Show the entire video, or have students view the video clips on the Web site and discuss the questions about each one. You may also show the first twelve minutes of the video and then view video clips 2 and 3 from the website. Have students respond to the questions on the handout. Discuss in class, if desired. Video clips are available at http://www.pbs.org/wnet/secrets/lessons/lp_bridge_videos.html.

9. As a culminating activity, have students take the interactive quiz at http://www.pbs.org/wnet/secrets/case_kwai/index.html.

Assessments:

• Students' participation in bridge building activity

• Discussion participation

• Completion of handout
Extensions:

• Have students complete these bridge-building activities from the following websites:

• Watch the video in its entirety. Direct students to the Web site, In Hell, There Is a Place Called the Death Railway at http://www.angelstation.com/swillner/index.htm. Have students write an imaginary journal describing what it may have been like to work on the Bridge on the River Kwai, from the perspective of either a POW or a Japanese officer.

• Research and report on the design and construction and safety of other famous bridges.

Correlation to National Science Standards:

From: http://bob.nap.edu/html/nses/html/6e.html#csc912

CONTENT STANDARD B: As a result of their activities in grades 9-12, all students should develop an understanding of ...
• Structure and properties of matter: An element is composed of a single type of atom. When elements are listed in order according to the number of protons (called the atomic number), repeating patterns of physical and chemical properties identify families of elements with similar properties.

• The physical properties of compounds reflect the nature of the interactions among its molecules.

• Motions and forces: Laws of motion are used to calculate precisely the effects of forces on the motion of objects.

• Gravitation is a universal force that each mass exerts on any other mass.

CONTENT STANDARD E: As a result of activities in grades 9-12, all students should develop understandings about science and technology:

• Creativity, imagination, and a good knowledge base are all required in the work of science and engineering.
CONTENT STANDARD F: As a result of activities in grades 9-12, all students should develop understanding of science and technology in local, national, and global challenges.

• Individuals and society must decide on proposals involving new research and the introduction of new technologies into society. Decisions involve assessment of alternatives, risks, costs, and benefits and consideration of who benefits and who suffers, who pays and gains, and what the risks are and who bears them.