Lesson Plan
Description:
This lesson is designed for collaboration of a 7th grade science and 7th grade
mathematics teacher. It is designed for teaching comparisons of fossil fuels to alternative
energy sources. The science component begins with a brainstorming activity where the
students are asked to think of all the different alternative energy sources they have heard
of. We will list the different answers the students come up with on the board and briefly
talk about each one, and compare and contrast alternative energy and fossil fuels. After
seeing what the students know, the lesson will focus on one specific source- solar energy.
There is a short video describing solar energy. Then students will use a graphic organizer
to list the advantages and disadvantages of solar energy. Next, the teacher will pass out
solar-powered outdoor lights. The students will dissect and examine the different
components of the light. We will briefly discuss how solar energy is transferred into light
energy by the outdoor light. We will finish the science section by discussing why we use
alternative fuels instead of fossil fuels.
The math component of the lesson will begin with the students making
hypotheses about the power usage of different appliances. They will create a data table
and calculate the daily cost of each appliance. They will then use their new skills to
create a graph of a linear system and analyze their graphs to answer questions.
Tools needed:
Science- graphic organizer, solar-powered outdoor lights
Mathematics- graph paper, several appliances, 4 usage monitors
Objectives:
SWBAT explain and understand the differences between fossil fuels and solar energy
SWBAT explain and demonstrate how solar energy works and is used
SWBAT use data to create a chart
SWBAT plot a linear system and analyze the meaning of the graph
7th grade Mathematics Standards:
7.EE.3: Solve multi-step real-life and mathematical problems posed with positive and
negative rational numbers in any form (whole numbers, fractions, and decimals), using
tools strategically. Apply properties of operations to calculate with numbers in any form;
convert between forms as appropriate; and assess the reasonableness of answers using
mental computation and estimation strategies.
7.EE.4.a: Solve word problems leading to equations
7th grade Science Standards:
E.SS 8.7.19 – conduct investigations demonstrating the greenhouse effect
E.SS 8.7.20 – research how human activities may contribute to global warning
PS 7.7.2 – describe alternatives to the use of fossil fuels
Possible Extensions:
-
Do similar projects but focus on hydro electric or wind or other alt. energy
sources that use generators specifically
Do a research project that deals with researching fossil fuels
Scaffolding:
Students must have the following skills to be able to do the activity:
-
The students must have an understanding of what fossil fuels are and how they are
created
The students must know the relationship between the greenhouse effect and the
burning of fossil fuels
Basic computational skills
Basic graphing skills
Alternative Energy
Solar Energy
Using your graphic organizer list as many
types of Alternative energy & Fossil fuel
sources as you can
3 min
List on board the different types of AE & FF
Solar, Hydro, Wind, Nuclear, Geothermal,
Biomass
Coal, oil/Gas & natural gas
Explain the difference between AE & FF
Both are used to produce energy (electricity)
FF also produces CO2, which pollutes the
air, soil & water.
Once a solar pannel is manufactured…
the AE does not pollute the air, water or
soil
But uses the air, water, soil and sun to
make energy **it does pollute some in the
manufacturing of many of these products,
especially any with batteries. The fact that
they are renewable is what makes them so
attractive to consumers (electricity)
Video (brain pop) Technology/energy
tech/solar energy
Adv & Dis-adv of AE
Pass out outside solar lights & let student
dissect. Explain how they work.
Q & A Section
Why do we/you use FF instead of AE
Cheaper & abundant (FF)
Using AE reduces CO2 into the Atmosphere
Reduces Acid Rain, Global warming, slows
down the Greenhouse effect
**making the batteries is bad for the
atmosphere. This is where the trade off is.
Recycling them is also very tricky
Solar Energy
Disadvantages
Advantages
Definition
Fossil Fuels
__________
__________
__________
Alternative Energy
_______________
_______________
_______________
Pre-Activity Questions:
1. Think about how much energy each appliance uses. Make a hypothesis of
which item uses the most power and which ones use the least. List the
appliances in order of their efficiency. Put the least efficient (most costly)
ones first.
Most power used
Least power used
2. Think about how much TIME you use each appliance each day. List the
appliances in order of the usage from most to least.
Most used
Least used
3. Now think about the total daily cost of each appliance. Order them based
off of their total cost per day to operate.
Most expensive
Least expensive
4. Estimate the daily cost to operate each of the appliances. Put your
answers in dollars. (Hint: assume a family spends $150 a month on their
electricity bill.)
APPLIANCE
TOTAL COST PER DAY
Appliance
name
Power
Power or
Measured by
current
Meter (in
(specified on
Watts)
appliance)
* energy (kWh) = (
𝑝𝑜𝑤𝑒𝑟 (𝑊)
1000
Estimated
time used in
a day (in
hours)
) (time used)
** Cost ($) = (kWh)(Cost of a kWH which is 8.7 cents)
Energy
consumed
each day
(in kWh)*
Daily Cost
(in Dollars)**
Graphing Activity
“Energy Star” water heater costs $789.00 for a 50-gallon tank. It uses 3500 watts of
power to operate.
“Energy Drain” water heater costs $248.00 for a 50-gallon tank. It uses 4500 watts of
power to operate.
1. If the average families water heater operates for 4 hours a day calculate the cost to
run each water heater per day.
Cost in Dollars = Watts/1000 X hours X 0.087
2. The average water heater lasts 10 years before needing to be replaced. Make a
table showing total cost of operation for 0 to 10 years for each water heater. Be
sure to include price of water heater.
3. Make a graph for each water heater on a coordinate grid. Use a different color to
plot the points for each water heater.
4. Write an equation for each water heater using the information in the table and
graph.
5. What are the coordinates for the point of intersection between the two graphs?
Explain what that point represents.
6. Which water heater would you buy? How much money would you save over the
10-year life of the water heater?
7. What if you knew you were going to move in 2 years and would no longer be
using the water heater, would that make a difference in the water heater you
decide to purchase? How much could you save by your decision?
8. If you were moving in 9 years which water heater would you pick
9.
How much money could you save in 9 years?