Site Overview

The Science and Safety of Electricity website is designed for students in grades 6 through 10. The site uses articles, experiments, and interactive games to teach students about the science of electricity, and how to use it safely in daily life.

Most of the site content is appropriate for students in grades 7 and 8, and meets several state and national science standards for those grades. Some articles and activities will also appeal to 6th graders. Science concepts and activities designed for older or more advanced students are identified with a “High Power” symbol. These meet several state and national science standards for grades 9 and 10.

Please note: Activities marked “GAME” are interactive. Other activities can be done in the classroom or at home with the materials listed (electrical components are available from Radio Shack). Most of the interactive games have some music built in. To turn the music off, click the speaker icon at the top right of the screen or turn off the computer speakers altogether.

The site is divided into five major sections of educational content:

• The Body Electric—Electricity and the human body
• World of Wires—The electric distribution system
• Dangerous Waters—Electricity and water
• You’ve Got the Power—Electricity in the home
• Fire in the Sky—Lightning and storm safety

Each of the major sections has five departments:

• Feature Story
• Do the Safe Thing
• Science Concepts
• Zapped! Activities
• Fantastic Facts

In addition to the major sections, the site contains the following:

• A summary of all the “Do the Safe Thing” safety tips from the site.
• A section called “Tell Me More About Electricity,” with detailed information related to electricity for further study.
• A list of links to pursue various topics in more depth online.
• A Games page with direct links to the three interactive activities and Trivia Game.
• This Teacher’s Guide.

Ideas for Classroom Use and Further Research

Do the Safe Thing Summary

Electric safety tips appear in each section of the site. For convenience, they also appear gathered together onto one web page called Do the Safe Thing Summary. Here are some ideas to help reinforce this safety information:

• Have each member of the class choose one safety tip from the site, do some further study and then make a report to the class on that tip.

• Do a simple art project in which each student picks a safety tip and makes a drawing to illustrate that safety principle. Post them in the classroom for a while as safety reminders.

• Have students find two or three ways electrical safety could be improved in their home.

The Body Electric

This section explains what electricity is and how it works in the human body. Science concepts focus on how the flow of electrons carries electric current, and understanding the difference between volts, watts, and amps. Safety tips focus on the dangers of electrical contact.

Overview of Activities in The Body Electric:

Keep Your Ion the Ball — This experiment tests the conductivity of a variety of beverages to see which ones contain a higher concentration of electrolytes, or salts.

Teacher Tips:

• Setup: Make sure students strip enough insulation from the ends of the wires to allow for good contact with the battery and the beverages. Remind them to wipe off the tips of the wires between each test.

• Question #3: Students’ answers to the questions will vary depending on the beverages they choose to test. Students may think that only salty tasting beverages will contain enough salts to make the bulb light brightly, but this is not the case. Any beverage with sodium, potassium, magnesium, and/or calcium will make the bulb light. Beverages with a higher concentration of these substances (such as orange juice and sports drinks) will conduct electricity better and should make the bulb light up more brightly than those with a lower concentration (such as water or tea). This may be a good opportunity to teach students the concept of concentration, which is a measure of the amount of dissolved substance contained per unit of volume.

Couch Potato Fitness: Too Good to Be True? — A research project on the effectiveness of muscle stimulators for losing weight.

(HP) Nervous Energy — An experiment using simple materials that simulates how nerve impulses travel from one neuron to another in the form of electrical signals.

Teacher Tips:

• Setup: Arrange the equipment exactly as shown and described. The experiment will not work unless all the connections are made correctly. In addition, the LED must line up with the phototransistor.

• Question #1. The hardware in this experiment models the parts involved in conveying nerve impulses from one neuron to another in the body. The batteries correspond to the neuron cell bodies. The wires attached to the LED correspond to the axon. The large LED corresponds to the axon tip. The space between the LED and the phototransistor corresponds to the synapse. The phototransistor and the wires attached to it correspond to a dendrite. And the electricity corresponds to the nerve impulse.

batteries = neuron cell bodies
wires = axons
large LED = axon tip
space between the LEDs = synapse
phototransistor = dendrite
electricity = nerve impulse

• Question #2. Just as a neurotransmitter is released by an axon tip and must cross the synapse to be received by a dendrite, so light from the LED must jump a gap in the circuit to travel through the air to the phototransistor.

• Question #3. The buzzer was used in this demonstration to verify that the signal was actually received by the phototransistor.

• Question #4. Students’ answers will vary regarding what the buzzer represents in the body. The buzzer is like the brain, which takes note of a stimulus. It could also be thought of as the body’s physical response to a stimulus.

Questions for Review/Discussion for The Body Electric:

1. Feature Story: How does the wire from Johnny Ray’s head allow him to play music in his computer? (It carries electrical impulses from an electrode in his brain directly to the computer.) What are some other possible uses for this discovery? (Other people with strokes or paralysis could use it.)

2. Science Concepts: What is the difference between a proton and an electron? (Protons are positively charged; electrons are negatively charged.) How do tiny electrons carry electricity? (When electrons get “bumped” from atom to atom in a conductor, electric current flows through that conductor.)

3. HP Science Concepts: What are some ways to help us understand and remember the difference between volts, watts, and amps? (Volts are a measure of the pressure of electricity, like the pressure of water in a garden hose. Amps are a measure of the amount of electricity, like the amount of water flowing through a hose. Watts are a measure of the work that can be done by electricity per second. Watts are a function of both the volts and the amps, just like the work you can do with a stream of water from a hose depends on both the amount of water coming out of the hose and the pressure with which it comes out.)

4. Do the Safe Thing: What is likely to happen to you if you contact electricity from a household appliance? (Heart attack or muscle contractions that lock you to the source of electricity.) What is likely to happen if you contact electricity from a power line? (Fatal shock or fall.)

Further Research for The Body Electric:

1. Are there other people besides Johnny Ray who have electrodes in their brains that help them work computers? Find one of them and write a report about that person.

2. What sorts of substances have loosely attached electrons? What does their atomic structure look like? What is it about these substances that make them good electrical conductors? Use the atomic diagram in “What Is Electricity?” as point of departure.

3. Do some library or Internet research to find an example of someone who survived an electric shock from a power line or an electric appliance. How did the incident happen? How could it have been prevented?

World of Wires

This section explains how electricity travels through power lines and home electrical systems. Science concepts focus on circuits and the difference between AC and DC current. Safety tips focus on overhead and underground power lines.

Overview of Activities in World of Wires:

Who Can Resist? GAME — This game teaches students how to build a simple electric circuit and then test a number of common objects to see if they are conductors or insulators.

Teacher Tips:

• Once the students have played online, it might be interesting to get the necessary parts and build a real circuit in the classroom. Use three pieces of 18- to 22-gauge wire with the ends stripped, a 6-volt battery, and a 6.3-volt screw-base lightbulb with matching base. Connect them as shown in the game. (In lieu of the lightbulb and base, you can cut up a string of mini-holiday lights and connect them to the battery, but be sure to discard the remaining lights when done for safety reasons.)

• Have each student bring in at least one object they think is a conductor and one they think is an insulator. An Altoids box is an interesting object: the painted outside is an insulator but the metallic inside is a conductor!

(HP) Electromagic — Your local utility delivers electricity to your home, but where does the utility company get the electricity? This activity explains electricity generation.

Teacher Tips:

• Setup: Make sure the compass and the nail are at least a meter apart; otherwise the magnet will directly affect the compass.

• Question #2: When students touch the ends of the galvanometer wire to the terminals on the D battery, they should notice that the needle will turn in one direction. This is caused by the direct current from the battery.

• Question #3. The current is direct current (DC); the needle moved in one direction only, just as DC current flows in one direction.

• Question #4: When the magnets are moved back and forth over the nail, the needle should move in one direction and then the other.

• Question #5: Students should be able to conclude that the current is flowing in one direction and then the other; thus, it is alternating current (AC).

• Question #6: A stronger magnet or more magnets would make the needle swing farther or faster. So would more coils of wire around the nail.

Questions for Review/Discussion for World of Wires:

1. Feature Story: Why are condors and other large birds killed when they land on power poles, while smaller birds are not? (Large birds’ wings can contact two power lines at the same time, creating a short circuit for electricity to flow through them. The same thing can happen if they contact a power line and power pole at the same time. Small birds do not contact anything but the power line they sit on, and so electricity stays in the line rather than flowing through them.) What is being done to prevent endangered condors from dying this way? (Aversion training teaches birds that will someday be released from captivity to avoid power poles. The birds get a small shock when they land on a simulated power pole.)

2. Science Concepts: What is a circuit? (A loop for electricity to travel on.)

3. HP Science Concepts: What is electromagnetic induction? (Using magnets to generate electric current in a wire.) How does the process work? (Giant coils of wire are moved past magnets. The pull of the magnets causes the electrons in the metal wire to move, creating electricity.)

4. Do the Safe Thing: Do you ever use ladders or long tools when working outside around your home? What precautions should you take to stay safe? (Answers will vary; precautions should focus on keeping all tools and equipment at least 10 feet away from any power line, including the line that leads from the power pole to the home.)

Further Research for World of Wires:

1. Research other efforts under way around the country to protect birds and other wildlife from dangerous electric power lines.

2. Learn more about AC and DC current. Why is AC current so much more dangerous to contact?

3. Find out how utility line workers protect themselves when working around power lines. What type of clothing, vehicles, and equipment do they use? What type of training do they receive?

Dangerous Waters

This section focuses on water and electricity. Science concepts focus on how to put out an electrical fire, and what a ground fault is. Safety tips focus on the dangers of mixing electricity with water and how to avoid this in the home.

Overview of Activities for Dangerous Waters:

You’re Grounded! — This project teaches about ground fault circuit interrupters (GFCIs) and then asks the students to search their home or school for GFCIs and perform a simple test to make sure they are working.

(HP) Famous Duo Splits Up — This activity shows how electrolysis works. Using test tubes and simple ingredients, students can separate the hydrogen and oxygen atoms of water molecules, producing hydrogen and oxygen gases.

Teacher Tips:

• Question #4: The test tube that contains more gas will be readily apparent; it is the one that has the largest air space at the top of the tube. The tube that contains hydrogen gas is the one that has the most gas in it. The tube that contains oxygen gas has less (about half as much).

• Question #5: Theoretically, another way to speed this reaction would be to use more electricity (not recommended).

• Question #6: If repeated with hydrogen chloride, you would get hydrogen gas in one test tube and chlorine gas in the other. Do not actually do the experiment with hydrogen chloride as chlorine gas is poisonous.

Questions for Review/Discussion for Dangerous Waters:

1. Feature Story: What are the different ways to light an outdoor swimming pool? (Wet niche lighting and fiber optic lighting.) How can it be safe to have electric lightbulbs underwater? (All the parts of the lighting system are kept dry and well insulated from the water.) What kind of lighting have you noticed in pools you have visited? (Answers will vary.)

2. Science Concepts: What should you do if an electrical appliance catches fire? (Use a Class C fire extinguisher to put it out.) What could happen if you throw water on it? (You could be shocked.) Why is that? (Water conducts electricity. Any electricity still flowing through the appliance can travel up the stream of water and shock you.)

3. HP Science Concepts: What does “grounded” mean when speaking about electricity? (Touching the ground or something in contact with the ground.) What are some ways you could be grounded? (Answers will vary. Make sure students know they can be grounded not only when standing directly on the ground, but when touching or standing on something in contact with the ground: holding or standing on a ladder, touching plumbing pipes, standing on the cement slab floor of a garage, standing on the sidewalk, climbing in a tree, etc.)

4. Do the Safe Thing: What is the safest way to use electricity in areas near water? (Make sure the appliance is plugged into a ground fault circuit interrupter, also called a GFCI. These devices monitor the flow of electricity in a circuit and if any is escaping the circuit, they quickly shut off power to prevent serious shock. GFCIs should be used with appliances in bathrooms, near kitchen sinks, and outdoors.)

Further Research for Dangerous Waters:

1. Find some stories about people who have been injured or killed by mixing water and electricity. Examples: stepping in a puddle with a fallen power line in it, or using a hair dryer in the bathtub and dropping it in the water. Why were these actions so dangerous? What lessons can be learned? (Use the Internet, library, or personal interviews to find these stories.)

2. What are some things you can do around your home to make it safer regarding water and electricity? Report to the class about a safety measure that you have taken at home.

You’ve Got the Power

This section talks about both electricity as it relates to our home environment. Science concepts focus on how utilities bill for power, and the importance of building codes (HP). Safety tips focus on inspecting the home for electric hazards.

Overview of Activities in You’ve Got the Power:

Breaker, Breaker! GAME. This interactive activity teaches about amps, watts, and what happens when you overload a circuit. The goal of the game is to try to get as many appliances as possible running without blowing a circuit. It has a good “under the radar” message about conserving energy, since the higher-drawing appliances tend to trip the circuit.

Teacher Tips:

• If you print out the amps calculation sheet ahead of time and make copies for all students, you will have a head start on the game. Students can take the time to do the calculations before starting to play.

• Encourage students to play the game more than once to see if they can learn from their mistakes and get a better score.

• Follow up with a discussion of whether students have ever blown a fuse or tripped the circuit breaker in their home. Which appliances did they have running at the time?

(HP) Save a Watt. This activity is a long-term homework assignment that teaches students about reading energy bills and conserving energy and money!

Teacher Tips:

• Make sure students understand why they should compare the same three months of this year’s and last year’s bills—so they are comparing periods that have roughly the same weather patterns and family habits.

• Make sure students are comparing actual energy used, not dollar costs. Help them look for these totals, which will show up in kWh and therms used.

• In some cases students may find that even though their household energy use went down for the months they saved energy compared to those months in the prior year, their bills went up due to increased energy costs.

• Some students may find that despite their energy conservation efforts they were not able to reduce household energy use compared to last year. Solving this mystery will take some detective work. Have students think carefully about the activities in their home that might have contributed to this. For example, if students had more people living in their home or visiting in the current year period, that means more energy was used to run dishwashers, clothes washers and dryers, and water heaters for hot showers. If the current year period was a lot hotter or colder than the prior year period, that means more energy was used to run the air conditioner or heater for longer periods of times or at higher settings.

Questions for Review/Discussion for You’ve Got the Power:

1. Feature Story: What kind of technology or new appliances would you like in your home to make your life easier, safer, or more fun? (Answers will vary.)

2. Science Concepts: How is electricity measured? (Kilowatt-hours, or kWh, which is 1000 watts used for one hour.)

3. HP Science Concepts: Why are building codes important? (These codes make sure buildings are constructed and repaired correctly. They ensure a building is safe for the people who use it.)

4. Do the Safe Thing: When was the last time you or your family members checked the cords on your electric lamps and appliances for cracks or worn spots? Do this as a homework assignment and report your findings to the class. (Answers will vary.)

Further Research for You’ve Got the Power:

1. Interview an electrician. What kind of training is required? What kind of licensing? Has she or he ever been shocked? How?

2. What are some building codes in your community’s building department that help ensure electrical system safety? Why are these codes important?

3. Look at your home heating and cooling equipment, water heater, clothes dryer, and oven. Which run on electricity? If your parents bought these appliances, talk with them to find out why they chose the models they did. What features were important to them?

Fire in the Sky

This section is about lightning, storm safety, and static electricity. Science Concepts focus on static electricity, and theories about the relationship of lightning to the origin of life (HP). Safety tips focus on what to do in a lightning storm.

Overview of Activities in Fire in the Sky:

Charge It! Static electricity is the buildup of electric charge on an object. In this activity, students build up electric charges on balloons and investigate the forces that they exert on other objects.

Teacher Tips:

• Setup: This activity will work best on a cold, dry day.

• Question #1: When students hold the balloon near their hair, the hair should fly up toward the balloon.

• Question #2: Students should be able to conclude that unlike charges attract. This may be a good opportunity to discuss the common phrase, “opposites attract.”

• Question #3: As you move one balloon towards another balloon that is sitting on a table, the balloons repel each other. This is because the balloons have like charges (in this case, both have a negative charge).

• Question #4: Just like the two balloons, the two strands of hair would repel each other. This is because they are both positively charged.

• Question #5: Like charges repel.

• Question #6: The paper sticks to the balloon.

• Question #7: The electrons, which are negatively charged, moved to the other end of the paper, leaving the positive charges closest to the balloon. This is why the paper was attracted to the negatively charged balloon.

(HP) A Little Lightning — Electric charges can build up on an object, but an object doesn’t stay charged forever. In this activity, students build up and discharge electric charges on objects. The activity simulates lightning by producing miniature “lightning bolts.”

Teacher Tips:

• Setup: Just like the activity above, this one works best on a cold, dry day. It is best if done in a room that’s pitch dark.

• Question #2: Students should see little sparks where their finger contacts the balloon. They should hear crackling noises.

• Question #3: In this activity, electric charge builds up when the balloon is rubbed against hair and picks up extra electrons. This charge gets discharged when you bring your finger close to the balloon, because then the excess electrons on the balloon jump back to your body.

Questions for Review /Discussion for Fire in the Sky:

1. Feature Story: Talk about a lightning storm that you experienced. What happened? Has anyone in the class ever seen lightning strike something like a tree or building? (Answers will vary)
2. Science Concepts: What is a common example of static electricity? (Your body can gather static electric charges by walking across a carpet. Then when you touch a doorknob or other conductive object, you make a spark and feel a small “shock” as the charges discharge or move to that object.)
3. HP Science Concepts: Is it possible lightning was involved in the formation of life? How could that be? Talk about it. (Discussions will vary. Emphasize that there are many theories about how life on Earth began, and this is just one of them.)
4. Do the Safe Thing: What’s the best way to stay safe when lightning is approaching? (Get indoors. Stay away from windows. Because lightning can travel through plumbing pipes and electrical and telephone wiring, stay away from tubs, sinks, anything electrical, and corded phones. )

Further Research for Fire in the Sky:

1. Find out the frequency of lightning storms in your community.

2. Has anyone in your community been struck by lightning? What were the circumstances? How was the person affected? How could the strike have been prevented?

3. During the buildup of static electricity, when electrons move from your hair to a balloon (or from the rug to your socks), does your hair (or your socks) maintain a positive charge? How does it get its electrons back?

It’s Not Trivial (Accessed from the Games Page)

This is a trivia game that tests what the students have learned on the website. There are questions from each of the main six content sections of the site. If the user gets a low score at the end, she or he is directed back to the site to learn more. Have students play the game once, and note their score. Then have students study the site again, play again, and see if their scores have improved.

Relevant State Standards for Grades 7 and 8

The Science & Safety of Electricity website contains information and activities that relate to the California Science Content Standards, Health Education Framework, and Language Arts Standards for middle school students. Relevant standards are listed below with links to corresponding site pages.

Science Content Standards

The Science & Safety site contains science information and experiments relevant to the Physical Science focus in 8th grade:

Structure of Matter

3a. Students know the structure of the atom, that it is composed of protons, neutrons, and electrons.

What Is Electricity?
Explains the structure of atom with an animated graphic.

Two Types of Current
Has more information on electron flow.

Charge It!
Uses experiment to explain the behavior of electrons as relates to the buildup of electric charge/static electricity.

Reactions

5a. Students know reactant atoms and molecules interact to form products with different chemical properties.

Famous Duo Splits Up
Includes an experiment about electrolysis (i.e., use of electricity to cause hydrogen and oxygen atoms in water to split apart.)

Periodic Table

7c. Students know substances can be classified by their properties including melting temperature, density, hardness, and thermal and electrical conductivity.

Keep Your Ion the Ball
Explores varying conductivity of different liquids in a hands-on experiment.

Who Can Resist?
Explores conductivity of common objects in an online interactive experiment.

World of Wires: Fantastic Facts
Contains information on superconductors and semiconductors.

Investigation & Experimentation

Several experiments and activities on the site address the investigation and experimentation standards for both 7th and 8th grade:

7b. Use a variety of print and electronic resources (including the World Wide Web) to collect information and evidence as part of a research project (7th grade).

The informational sections of the site (i.e. the feature articles, science concepts, safety tips, and facts) are helpful for research projects about electricity and electrical safety.

The Tell Me More section was designed to help students researching electricity generation and distribution, alternative energy sources, electric vehicles, and careers in the electric industry.

The Teacher’s Guide contains ideas for research projects: finding someone who survived a shock from a power line or appliance; finding out about efforts to protect birds and other wildlife from power lines; finding stories about people who have been injured or killed by mixing water and electricity; and interviewing an electrician.

7e. Communicate the steps and results from an investigation in written reports and oral presentations (7th grade).

Any of the activities and experiments on the site could be described in a written report or oral presentation.

9a. Plan and conduct a scientific investigation to test a hypothesis (8th grade).

The following experiments require students to test a hypothesis:

• Keep Your Ion the Ball
  
• Electromagic
  
• Who Can Resist?
  
• Charge It!

Health Education Framework

The Science & Safety of Electricity site has electrical safety tips and principles that help satisfy Health Education Expectation 3: The student will understand and demonstrate knowledge of behaviors that reduce the risk of becoming involved in potentially dangerous situations and know how to react to situations in ways that help to protect his or her health. Students in middle school who meet this standard will be able to:

Analyze emergencies and respond appropriately.

Watch Those Wires
Teaches proper response to downed power lines, unlocked transformers, and person entering substation.

Electricity + Water = Danger
Teaches what to do for an electrical fire.

Identify behaviors that decrease the risk of becoming involved in potentially dangerous situations.

Electricity + Water = Danger
Teaches safety tips about using electricity around water.

Home Safe Home
Includes a home inspection to identify electrical hazards.

Lightning Fact or Fiction?
Lightning Tips
Explains how to avoid lightning.

Explain the need for using protective equipment in sports and physical activity or practicing behaviors that protect the body.

Electricity Is Shocking
Explains how electricity can hurt you and the need for safety measures.

Teacher's Guide
Includes a research assignment to find out how utility line workers protect themselves with clothing, vehicles and special equipment when working around power lines.

A complete list of all safety tips on this site can be viewed at the Do the Safe Thing Summary page.

Language Arts Content Standards

Language Arts standard 2.0 for Reading Comprehension focuses on informational materials in both 7th and 8th grade. The Science & Safety site is an informational resource for teaching reading comprehension:

2.0 Reading Comprehension (Focus on Informational Materials)
Students read and understand grade-level-appropriate material. They describe and connect the essential ideas, arguments, and perspectives of the text by using their knowledge of text structure, organization, and purpose... students read one million words annually on their own, including a good representation of narrative and expository text (e.g., classic and contemporary literature, magazines, newspapers, online information).