Diverting Disaster With Lightning Rods

Before/Engage:

1. Ask students if they have ever shocked themselves or someone else by dragging their feet across the carpet and then touching something. Have partners turn and talk about a time this happened and ask if students know the name of that phenomenon (static electricity).
2. Create static electricity by rubbing a balloon on a piece of wool or someone’s clean, dry hair. Have students listen for the crackling sound, and turn off the lights to see if sparks can be seen. Scatter small pieces of paper or confetti on a table and use the charged balloon to pick them up. Have students turn and talk about the demonstration and how they think static electricity is like lightning. 
3. Make a class Venn diagram on the board or chart paper to compare static electricity and lightning. Have students write their thoughts on sticky notes to post on the diagram so these can be moved if students revise their thinking throughout the lesson.
4. Watch 2-minute PBS video to explain lightning.
5. Direct students’ attention back to the Venn diagram and allow students to correct any misconceptions they may have had about lightning before watching the video.
6. Work in groups of 4 to brainstorm possible problems or hazards caused by lightning. Have students share their ideas with the whole group. Tell students they will be learning about ways to protect structures from lightning-caused fires.  

During/Explore/Explain:

1. Divide students into heterogeneous groups of 4. Distribute materials for "Make Lightning" activity from STEM-Works (styrofoam plate, pencil with eraser, thumbtack, aluminum pie plate or foil folded into a 6" disk, and wool cloth).
2. To simulate lightning, have students create a handle for the pie plate by pushing a thumbtack through the center into the pencil eraser. Rub the Styrofoam plate with wool for one minute. Place the pie plate on the styrofoam plate using the pencil as a handle. Touch the metal plate to see a spark jump toward your finger. (You may want to turn off the lights so the spark is easier to see.)
3. Explain how this spark of static electricity simulates lightning by reading the explanation on STEM-Works. Make adjustments to class Venn diagram as needed.
4. Give two students in each group the "How Lightning Rods Work" passage and give the other two students the "Thunder and Lightning" passage. (The "Thunder and Lightning" passage is on a third-grade reading level, while the "How Lightning Rods Work" passage is on a fourth-grade level, so assign passages to students based on their reading levels for maximum comprehension.)
5. Tell students they will use the jigsaw strategy to learn more about lightning and lightning rods. The two partners with the same article read the article together, underlining important facts and making notes in the margins so they can share their learning with the group. After each set of partners has read their passage, the group of four will meet together to teach each other the information learned from the passages.
6. Debrief by having groups share important information learned with the whole class to ensure each group focused on the important information. Project the "How Lightning Rods Work" passage on the interactive whiteboard and discuss the diagram, pointing out that metals conduct electricity while wooden parts of the home do not and are flammable. Have students adjust the Venn diagram as necessary, adding new information or changing the location of the sticky notes to reflect their learning.
7. Project the PBS Lightning Rod Simulation on the interactive whiteboard and complete it as a class. After guiding students through the simulation as a class, students can return to the site later for independent practice.

After/Explain/Extend:

1. Review the facts about the lightning rod system:

• • The rod, wire, and ground rod must be metal so they conduct electricity.
  • The ground rod carries the electricity into the ground and away from the building so the wood does not catch on fire.

2. Tell students they will use craft materials and recyclable items (empty cartons, boxes, paper towel rolls, water bottles, etc.) to construct a building with a lightning rod system in their cooperative groups of 4. After constructing the building and lightning rod system, the class will evaluate each group's design to see if it would be effective in preventing a lightning fire.

3. Remind students to refer to the "How Lightning Rods Work" passage as they create their model homes to ensure that they create all parts of the lightning rod system.  

4. Have groups present their structures to the class, explaining what type of building they created and how the lightning rod system works. After each group presentation, have students vote (with thumbs up or down) whether they think the lightning rod system would protect the building from fire. As groups present, complete the Assessment Checklist for each student.