SOURCE Lesson Plans Detail

Designing Reliable and Resilient Truss Based Bridges

Topic Engineering Design, Structure, Material Economics Learning Exchange Program Hoang Nguyen Elementary students

Overview / Purpose / Essential Questions

This lesson plan aims to introduce students to fundamental structures that engineers utilize in their projects. One such structure is the truss, a simple structure that can be manipulated to produce formidable structures. In this project, students cement what they learn about stable structures in a hands-on bridge building project.

Performance / Lesson Objective(s)

• Understand what makes trusses strong
• Minimize material usage and optimize structure functionality
• Introduce the idea of joint analysis at a very basic level

Lesson Materials

• Popsicle sticks
• Hot glue
• Super glue
• Zip ties
• Dry erase board
• Dry erase markers

Lesson Motivation

This lesson is largely motivated by the desire to have students apply concepts they learn, the theory and facts about structural stability, in practical ways. By having students model a bridge, designed specifically to withstand a load, they will have gained an insight into the realm of physics. Keeping it elementary, we hope to introduce concepts as fundamental as Newton's laws of motion so as to help students understand them in a materialized fashion. By seeing their bridge fail or succeed after having the loads applied, they will conceptualize physics at play.

Lesson Activities

• Designing individual models on dry erase boards
• Modifying designs based on "lectures"
• Building
• Testing
• Reviewing concepts

Procedure

1. Have students draw/design what they initially believe to be a stable bridge.
2. Give lecture about the importance of trusses in a bridge structure
3. Have students modify their designs
4. Once students are ready, have they present their designs supplemented by an explanation of stability. Use Socratic method to suggest further improvements.
5. Once they have a final design, provide them with a fixed amount of Popsicle sticks they can use, and have them start building their bridges.
6. Construction comes in three phases: building the bottom/base, and the two sides.Use zipties to bind the components together.
7. Once every student has a final structure, have them speculate the best performing structure.
8. Test the structures, one by one, by wrapping a bucket to the bridges. Incrementally put books into the bucket.
9. Record all the results
10. Have students examine and analyze their findings.

Wrap up / Conclusion

Students were engaged while completing this project, and at the end, they were all able to gain a notion of Newton's laws. While they were not able to explicit explain the principles, they often invoked their projects, explaining the principles very crudely in terms of how they were related to the success/failure of their projects.

Alignment Info

Audience(s) Middle school students PhysicsEngineering Physical Sciences (RI GSE) PS3.5-6.8bStudents demonstrate an understanding of force (e.g., friction, gravitational, magnetic) by… recognizing that a force is a push or a pull. Hands-on 678 1 01/23/2015 06:32 PM 12/20/2018 11:40 AM