Towers - Lesson Plan
Getting Ready
- Build your earthquake shake table (See Sources section).
- Prepare the sand bags.
- Do a trial run with a structure of your own design to see where students may run into trouble. Securing the structure to the foundation and securing the joints are two areas where students run into trouble.
Lesson Plan
- Introduce the project to the students.
- Explain the rules and requirements.
- Demonstrate the testing procedures and show how the shake table works.
- Show students some of the different methods for joining straws together without folding the straws and compromising their integrity.
- 2 straws may be pinned together with a straight pin.
- A paper clip may be partly opened up – the inner U pulled out from the outer U – and each U may be slipped into a different straw.
- Holes may be drilled with the pins and the string slipped through to tie straws together.
- Allow students to begin designing and building.
- Interrupt class at once or twice a class period for 5 minute “teaching commercials” based on various successful student designs or to combat problems multiple teams may have encountered. Some of the teaching commercials I included were:
- Strategies for how to secure the structure to the foundation using paper clips, pins and/or string.
- Would a better structure have a wide base of a narrow base?
- Would a better structure be symmetrical or asymmertrical?
- A description of trusses and cross-bracing and discussion of their use in bridges, earthquake retrofitting, and other structural engineering.
- How can you secure the sand bags so that they don’t fall off?
- Test the structures. I chose to have students test their structures as they finished. This allowed for groups to work at different paces and reduced the overall number of days the students spent on this project. Another option is to require all teams to finish building on the same day so that testing could occur on the following day. In this way, all students can watch the others and make observations about the different structures, noting what worked and what didn’t.