Mystery Class Update: March 2, 2001

Today's Report Includes:

Four for Four
Time is really flying! It's now the fourth week of Mystery Class, and your Mystery Friends have submitted their fourth set of sunrise/sunset data for you from around the globe.

Have you figured out which location is the farthest north? The farthest south? The closest to the equator? Can you put them in a north/south order now? Where is your hometown in that order?

Countdown to Clues
In two weeks, you'll start to receive a little help with your global search. On March 16, you'll get the first set of clues, which will give you everything you need to estimate the approximate longitude of the Mystery sites.

Teacher Tip: Longitude & Literature

"For the first time this year, students had no trouble understanding the longitude calculation and why it might be east or west of Greenwich depending on the direction of time difference." Kathleen Isaacs

To help students understand some fundamental ideas about longitude before the clues arrive, you might want to look at the literature suggestion from Washington, D.C. Teacher Kathleen Isaacs of Edmund Burke School:

The Sun's the One! Discussion of CQ #2
Last week we asked "How do seasonal changes in photoperiod affect your animal's food web?"

Generally speaking, the longer the photoperiod, such as in spring and summer, the more food that will be available. This is because the added sunlight and heat in spring and summer make plants grow, and the plants provide food for plant-eating animals, and these plant-eating animals can then be available as food for animals which prey on them. Also, the added sunlight and heat warm the air and thaw frozen soil and lakes, making other foods such as worms, insects and fish available too.

On the other hand, the shorter the photoperiod, such as in fall and winter, the less food will be available. The reduced amount of sunlight and heat means fewer plants are available for plant-eating animals, and fewer worms, insects and fish too, and therefore less food is available for animals that prey on these food sources.

Many students described how the seasonal changes affected the food web of their animals. Here are a few students who really "saw the light" when answering Challenge Question #2:

Ms. Hall's Grade 5 class from Scarborough, Ontario wrote about the robin:

"We think the amount of sunlight is related to the robin's food-web because as the amount of sunlight increases so does the average temperature outside. As the temperature rises, the snow and ice melts allowing the ground to thaw and the earthworms to emerge. Also when there is less sunlight, other sources of food for the robins fade (berries, seeds) so they must migrate to areas where food is more available. Added to this, the sun helps the plants to grow that the robins feed on." Tom Longboat P.S. in Scarborough, Ontario (Alison.Hall@etel.tdsb.on.ca)

The "scientists" in Mrs. Koontz's Third grade class from Bowie, MD described the effect on the red-winged blackbird:

"The red-winged blackbird eats seeds and insects. The seeds grow on trees and bushes so when the photoperiod gets shorter there is less sunlight for the seeds to grow. The insects die or migrate underground in the winter. To find food the red-winged blackbird migrates south just like the monarch." (fkoontz@pgcps.org)

And Miss Bailey's class from Vero Beach, FL wrote about hummingbirds and "little animals":

Lauren said: "When the seasons change the sun gives less energy and it is bad for the flowers because it makes the flowers grow slower and the hummingbird cannot nectar."

And Anteria wrote: "Little animals eat plants, and the sun will give energy to the plants. If you get more sun the plant will grow faster but if you get less the plant will not grow more." (bailey_a@popmail.firn.edu)

This Week's Sunrise/Sunset Times
Remember, the secret Mystery sites recorded their times last Monday, the same day you collected your own local sunrise/sunset data.

Journey North Mystery Class

Sunrise/Sunset Data

Data For: Monday, February 26, 2001

 MYSTERY CLASS SUNRISE SUNSET #1 07:13 18:26 #2 07:25 19:28 #3 06:29 19:25 #4 07:03 18:46 #5 04:35 23:29* #6 06:52 17:36 #7 07:03 20:04 #8 06:47 18:26 #9 06:32 18:59 #10 06:53 18:03

* Mystery Class #5 wanted you to know: "At long last...it happened! For the first time in months, the sun finally set!"
Note: Military time is usually expressed without any punctuation. We have used a ":" between the hours and minutes for clarity.)

The Next Mystery Class Update Will be Posted on March 9, 2001