The SafeTreeKids website uses information
and activities to teach students the value of trees and the dangers
of climbing, planting, or trimming trees near electric power lines.
The site is geared for 4th grade use; however, it can accommodate
a range of interests and reading levels. (Nonreaders will be able
to play the games with adult assistance.)
Part I of this Teacher's Guide describes
the contents of each section of the website. Part II contains questions
and activities teachers can use to focus students' attention on
key safety messages.
I. SITE OVERVIEW
• Trees and Power Lines
How trees near power lines can cause electrical outages, fires,
• Trees Are Awesome
What trees do for us. The parts of a tree and their functions.
Dendochronology: the study of tree rings (includes a tree-ring mapping
activity). Safe tree trimming.
• Electricity Can Hurt
How the human body can conduct electricity; what electric shock
• Electricity Basics
How electricity is made and how it travels through the power line
distribution system. Energy-saving tips for students and their families.
• SafeTree Safety Tips
Top 10 tree/power line safety tips, plus a checklist that students
can use with family or friends who plant a tree.
• Find the Hidden Dangers Game
Students use the safety principles they have learned and put them
into practice to identify tree/power line hazards in a busy neighborhood
• Safety Certificate
Summary of 5 key tree/power line safety facts that students should
understand when they come away from this website. Certificate has
space for adult signature to encourage parent and teacher involvement.
Definitions of unfamiliar words found on the site.
• Links to Related Sites
Hot links to related websites about trees, the science of electricity,
and electrical safety games.
II. QUESTIONS AND ACTIVITIES
These 20 questions review the key safety
principles from the SafeTreeKids site. Here are a few ideas for
how to use them with your class:
• Use as discussion points to verbally
review basic electrical safety information with the whole group.
• Use as a pre- and post-test to assess
student understanding of tree/power line safety principles before
and after visiting the site. (To use as a written test for older
students, cut and paste the questions into your word processing
program, delete the answers, and print out one sheet for each student.)
• Put students into small groups and
assign each group several questions; ask them to use the website
to find the answers.
• After all students have completed
all sections of the website, organize the class like a game show:
"contestants" can continue to answer questions until they get one
incorrect, at which point a new contestant takes their place.
Basic Electrical Safety Questions
1. What does electricity travel on to get
from the power plant to people's houses? (Overhead and underground
2. Which wires on power poles are the high-voltage
ones? (The high-voltage lines are at the very tops of the poles.)
3. Is it okay to contact the power lines
that are low on the pole, or the service drop wires that carry electricity
from power poles to buildings, and that look insulated? (No, all
lines and equipment on power poles are dangerous to contact. Some
lines may appear to be insulated, but it's just weatherproofing.)
4. What other equipment is involved in
getting electricity to where it can be used by people? (Some or
all of the following are correct: substations, pole-mounted and
pad-mounted transformers, service drops, meter boxes, electrical
wiring, appliance cords.)
5. What are two good conductors of electricity?
6. Is the human body a good conductor of
electricity? Are trees good conductors for electricity? Why/why
not? (Yes for both, because they both contain a lot of water and
water conducts electricity.)
7. What will happen if electricity travels
through you? (You will be shocked and could be badly hurt or even
8. Do you have to be touching the ground
directly to conduct electricity? (No, you could be touching something
that is touching the ground, like a ladder or a tree.)
9. If a person is shocked, what can happen?
(Muscle spasms, weakness, shallow breathing, rapid heartbeat, unconsciousness,
10. Why can birds sit on power lines without
being shocked? (The birds do not touch the ground or anything in
contact with the ground, so electricity stays in the line and does
not pass through them.)
11. Can fallen power lines hurt you even
if they are not sparking or humming? (Yes! That's why you should
stay away from them and tell an adult right away.)
Tree/Power Line Safety Questions
12. How can trees near power lines cause
electrical outages? (If a tree branch contacts a power line, safety
devices shut off electricity to the line. Then electricity goes
off in buildings served by the power line.)
13. How can trees near power lines cause
fires? (If a tree branch touches a high-voltage power line, the
electricity can heat up the branch so much that it catches fire.)
14. How can trees near power lines cause
shock hazards? (Trees are great conductors for electricity. So if
a tree branch touches a power line, electricity will go through
the tree to the ground, and anyone who touches the tree could be
hurt or killed by electric shock. Or, someone could climb a tree
near a power line and actually touch the line, which would also
result in serious shock.)
15. What would happen if a tree branch
were to knock a power line to the ground? (It would energize the
area around it with a lot of electricity and people touching the
line or coming near it would be hurt or killed. It could also cause
an outage and/or a fire.)
16. Why should untrained people NOT trim
trees near power lines? (It's just too dangerous. They could contact
the line by mistake and be hurt or killed.)
17. Who should trim trees near power lines?
(Only professional tree trimmers who are certified to work near
18. What should your parents do if they
see a tree growing close to a power line? (Call Pacific Gas and
Electric Company at 1-800-PGE-5000.)
19. When is it okay to play in a tree growing
next to a power line? (Never! Trees near power lines are very dangerous
to climb or play in.)
20. Why is it important to call 1-800-227-2600
before planting a tree? (So you can make sure you won't contact
underground power lines or other buried utilities when you dig.)