# Predicting the Arrival of Spring

Background
"The seasons, like great tides, ebb and flow across the continents. Spring advances up the United States at the average rate of about 15 miles a day. It ascends mountainsides at the rate of about a hundred feet a day. It sweeps ahead like a flood of water, racing down the long valleys, creeping up hillsides in a rising tide."

So begins the book, North With the Spring (St. Martin's Press, 1951), by Pulitzer Prize winning author and naturalist Edwin Way Teale. One spring in the 1950's, Teale criss-crossed the United States on a 17,000 miles journey north with the season. The trip is described beautifully in his book.

How long do you suppose it will take the spring of 1997 to cross the continent? Imagine counting the days, in 15 mile/day intervals, as spring travels northward from one school garden to the next. The lesson below should be conduced at least twice during the year. Each time, students can predict the date tulips will bloom:

• In their own gardens
• In their partner school's garden
• At 10 selected sites in North America. (See map .)

Students will enjoy noting how their predictions improve as they learn about:

• The conditions that affect plant growth and
• The climatic regions of North America.

Materials:
1. Wall map of North America
2. Post-it notes (or blank mailing labels, or slips of paper and tape )
3. Graph paper
4. Crayons, markers, or colored pencils

Activity :
This activity should first be done before planting your garden and even before the planting instructions are reviewed. The second prediction can be made early next spring, before tulips bloom anywhere in North America. Predictions should be revisited and revised throughout the spring months, as new information becomes available to students.

Part I: Making Predictions
1. Organize your class in pairs or groups of four. Play up the fun of making a prediction before collecting information. Students will discover how much they have learned during the year. They can gather the information they need to refine their hypotheses and make a second prediction.

2. Each group or team should predict the date they think tulips will bloom:

• In their own garden
• In their partner school's garden (See below.)
• In the following 10 places in North America:
Palo Alto, California
Washington, D.C.
Boston, Massachusetts
Mahnomen, Minnesota
Mississauga, Ontario
Portland, Oregon
Nashville, Tennessee
Houston, Texas
Salt Lake City, Utah

Give student groups a copy of the map. Have each group record their reasons for guessing as they have.

3. Students can use "post-it" notes (or other labels) to record the date guessed for each of the 10 sites. After all predictions have been made, students can post them on the map of North America.

Part II: Graphing
1. The following graph should be drawn on the board or on a large piece of tag board. Students can post their dates in the proper area of the class graph.
 Feb March April May June Anchorage, Alaska Palo Alto, California Washington, D.C. Boston, Massachusetts Mahnomen, Minnesota Mississauga, Ontario Portland, Oregon Nashville, Tennessee Houston, Texas Salt Lake City, Utah

2. Next, each student or group should calculate the average date your class guessed for each city.

3. These graphs & estimates should be saved for use next spring when students are given additional opportunities to make predictions. The data can also be exchanged with a partner school as discussed below.

Discussion Questions :

• What is the earliest prediction? The latest?
• What is the average date guessed for each city?
• How did each group decide the date to predict for each area?
• What information would have been helpful for making better predictions?
• Do you think tulips are good indicators of spring? Why or why not?
• How might this experiment be refined to measure spring's advance more accurately?
Exchanging Data With a Partner School
1. Watch for a posting in December of all schools participating in this project.

2. Before selecting a school to contact, ask your students to consider these things:

• What information would be valuable to exchange?
• From which geographic regions would the data be most interesting?
• Why might it be interesting to exchange data with a school in your own town?

3. If students choose to exchange data & predictions from this lesson, ask them:

• How are the predictions made by both classrooms similar and how are they different?
• Why do you think so?
regions of North America.