Journey North Mystery Class Spring 2004

Mystery Class Update: February 13, 2004

Today's Report Includes:

Just in Time for Valentine's Day
Oh Mystery Class . . . Whereforart Thou?
Teacher Tip: Graphing Photoperiod
Reasons for Seasons: The Astronomy of Spring
Who Knows What Time It Is? Discussion of CQ #1
This Week's Sunrise/Sunset Times
Note to Teachers: Plan Ahead and Mark Your Calendars

Just in Time for Valentine's Day
Every year around this time, candy, flowers, and gifts are exchanged between loved ones, all in the name of Valentine's Day. And this year is no exception because your secret mystery friends have sent you a gift of their latest sunrise/sunset data.

Remember this information was recorded on Monday, February 9, 2004, the same day you collected your second set of hometown sunrise/sunset data.

Mystery Class, Oh Mystery Class . . . Whereforart Thou?
As you plot this week's data on your graph, ask yourself the following questions. Can you determine:

1) Where is photoperiod changing the most quickly?

2) In which places is it increasing? In which places is it decreasing?

3) What might these things tell you about the location of each site?

More Tips from the Pros
If you haven't already read her insights, Nebraska teacher Gayle Kloewer has some suggestions to help students get the most out of graphing in this Teacher Tip:

Teacher Tip: Mystery Class/Graphing Photoperiod

Reasons for Seasons: Exploring the Astronomy of Spring
As you begin to notice changes in your graph, now is a good time to explore why we have seasons and changing day length. Many people have misconceptions about this. The real reason for seasons lies in the fact that the Earth is tilted on its axis. The tilt of the Earth affects the length of days and also the amount of direct sunlight received during the seasons. Take a look at the lesson below called Reasons for Seasons:

Reasons for Seasons

We always welcome tips from practicing Journey North teachers. Please share your ideas! jnorth@learner.org

Who Knows What Time It Is? Responses to CQ #1
Last week we asked about the meaning of two expressions that most people use everyday, but probably never stop to think about: "What do the initials 'A.M.' and 'P.M.' stand for anyway?"

We had many correct answers from students across the United States from Arkansas to Wisconsin. Several answers took us for a quick Latin lesson on the meaning of these expressions:

The 3rd Grade Discovery Class from Hambrick Elementary School in Stone Mountain, GA wrote that: "A.M. stands for ante meridian (before noon).P.M. stands for post meridian (after noon or after the sun has passed its highest point). The Latin is ante meridiem and post meridiem. "

Mrs. Berlin's Third Grade Class in Framingham, MA knew that a.m. meant morning, and p.m. afternoon, but they went to their dictionaries and learned that a.m. was the abbreviation for ante meridiem, a Latin word meaning before midday. P.M. is Latin for post meridiem meaning after midday.

Emily from Denver, CO wrote that "A.M. and P.M. stand for the Latin words ante-meridiem and post-meridiem meaning being before noon and being after noon."

Ms. Goforth's class at Fairview Elementary in TN answered that "a.m. means before noon in Latin, ante meridian p.m. means post meridiem in Latin, being after noon."

Mrs. Lodge's classes in Hebron, CT were packed and ready to move into a new school. They unpacked their dictionaries to answer that "A.M comes from the Latin for ante meridian, it is the time from midnight to noon. P.M. is from the Latin for post meridian, the time from noon to midnight."

Our thanks and congratulations to all the students who answered Challenge Question #1. Nice job everyone! We wish we had space here to list all your answers.

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.

Link to This Week's Sunrise/Sunset Data

Note to Teachers: Plan Ahead and Mark Your Calendars
Here's the 2004 Mystery Class Schedule so you know what to expect from Journey North. Please be sure to plan ahead.

February 6- April 16:	Each Friday, Sunrise/Sunset Times are posted for the ten Mystery Sites.
March 12:	The "Longitude Clue" is posted.
March 19, 26, April 2, 9 & 16:	Interdisciplinary clues from the Mystery Sites are posted each week. (Please Note--out of fairness to all participants, we will only post the clues on their scheduled dates.)
April 23: Deadline for Your Answers!	No late entries will be accepted (out of fairness to all participants, no exceptions.)
April 30:	Mystery Sites Revealed!
May 7:	Meet Your Mystery Friends!

The Next Mystery Class Update Will Be Posted on February 20, 2004