Light and Shadows
S. Mackey Black Gold Regional Schools
June 2006

Have you ever noticed how  shadows change? Sometimes they are
longer, sometimes they are shorter, and sometimes they seem
to disappear!

Find out what causes this to happen. You will collect data to find out
why your shadow changes throughout the day.

Task

bulletWork collaboratively with another student in the class.
bulletgather photos of your changing shadows
bulletMeasure your shadows and graph them using line and bar graphs
bulletCreate a short PowerPoint presentation to present your findings

Process

Step #1 Learn more about Shadows

Use the following websites to discover learn more about Shadows:

bullet Light and Shadows
bullet How We See Things
bullet Measuring With Shadows

Step #2  Measure and photograph your Shadows

bulletChoose or be assigned objects around the school to watch (examples might include a bench,
a flag pole, a fence, tree, etc.) at certain times of the day (9:00 a.m., 12 p.m., and 3 p.m.).
bulletYou and your partner will record your findings. Using your metre stick, measure from the base
of the object along the ground to the tip of its shadow.  Record the length of the object's shadow
on your paper as well as any other significant changes in the shadow.  For example, if the sun is in
the eastern sky, the shadow will be pointing west. This information needs to be recorded on the
attached Shadow Data Sheet. This Data Sheet will need to be printed out. Make sure to be as
precise in your measurement as you can be! If you measure the first shadow in cm, make sure
you continue to use cm.
bulletUse a digital camera to record what the shadow looks like. (This activity will be completed over a period
of three days to allow all groups time to photograph and compare the photos.)
bulletDescribe where your object is located, make sure you record the dates and times you watched your item,
 the weather and changes that you observe.

Step #3  Enter and analyze your data

bulletOpen a new document on Microsoft Excel. (Sample template). Using your information
gathering sheet, record your data. Once you have entered your data create at least 2
 different graph types to display your findings.

Step #4  Present your findings

bullet In order to successfully create a Power Point that will present your information, you and your partner
 must work together, using all of the information you have found. You must compare the information you
 have found and create a presentation that will show some information about shadows, show your shadow
 photos, and then present data to uphold your findings of how shadows grow, shrink and disappear.

Your Power Point should include:

bulleta title page (include the names of your group members)
bulletan information page to include what your object was and where it was located,
bulletseveral data pages (no more than 4, showing some or all of the photographs you have taken)
bulletGraphs detailing the changes in the shadow
bulleta summary page/conclusions (explain why your shadow changes size, and the role the sun plays in your
 shadow's length.)

Extension *** Students can take these measurements three times throughout the year, (Sept., Jan., May),
transfer data to a spreadsheet, create graphs and compare the effects of the sun's movement throughout
the day in different seasons.

Evaluation