Lesson LEAFlet

Teaching/Learning Resources

Subject Area:

Science

Grade Level:

K - 8

Curriculum Integration:

Chemistry and Earth Science

Lesson Objectives:

1. Help students understand the greenhouse effect as a physical phenomenon.

2. Use simple experimentation techniques including: observing and recording data, use of a
control, drawing conclusions from results, use of a model.

Materials Required:

For every group of (about) four students:

2 Small thermometers
1 Jar or other see-through container
1 Clock or watch
1 Copy of the worksheet
Sunlamp or access to a sunny area to perform the experiment

Lesson Outline:

Method:

Group the students and distribute the materials. Each group should place their thermometers a
few inches apart under the sunlamp or in direct sunlight.

Wait about three minutes so the thermometers will be giving accurate readings, and then have the
students record the temperature readings on both thermometers as well as the time.

Each group should now place their jar over one of their thermometers, taking care that the jar
does not cast a shadow over the uncovered one. If the thermometers are too large to remain
horizontal inside the jars, it is fine to stand them against an inner side. Every minute, for ten
minutes, the students should record the readings of both thermometers.

Explanation

The air over the exposed thermometer is constantly changing, and as it gets warm it is replaced
by cooler air. Because the air in the jar cannot circulate to the rest of the room, this air stays in
the sunlight and gets warmer and warmer. A similar trapping of heat happens in the Earth's
atmosphere. Sunlight passes through the atmosphere and warms the Earth's surface. The heat
radiating from the surface is trapped by greenhouse gasses. Without an atmosphere, the Earth's
temperature would average about 0F. This warming due to heat-trapping gasses is called the
"Greenhouse Effect." Both the atmosphere and the jar allow light to enter, but then trap that
energy when it is converted to heat. They work differently, however, because the jar keeps in the
heated air, while the greenhouse gasses absorb radiative heat.

Instructions

Place the two thermometers in the sunlight for a few minutes to let them get warm.
Record the readings of both thermometers at the top of the columns.
Record the time next to the starting temperatures and place the jar over thermometer #1.
Every minute, record the readings of both thermometers without disturbing them.

Data

Time	Observation Number	Thermometer #1	Thermometer #2
1
2
3

Extension Activities:

Students can graph their data. To simulate global warming, the experiment can be done using
two jars, one filled with air and the other with carbon dioxide.

Submitted by:

Jason Gerle, Racheal Berry, Heather Hogue, and Paula Braendel

Composed by:

Franklin Institute
http://sln.fi.edu/tfi/activity/earth/earth-5.html

For:
Lake Erie Arboretum at Frontier Park

Send plans to:

Dr. Charles Elliott, Director
       Educational Technology
       Gannon University
       109 University Square
       Erie, PA   16541