Date: October 16, 1997

Subject(s):

• Science/Agriculture

Duration: 45 Minutes

Overview:

In this elementary science activity, students will have an opportunity to note the attributes, likenesses, and differences among pumpkins they have brought back to the classroom from a trip to a pumpkin farm. They will learn that all pumpkins are different. They vary in size, weight, and the number of seeds found inside. Students will practice several scientific processes, including observing, predicting, and recording observations as a pumpkin is examined.

This lesson is planned as a follow-up activity for students who have visited an authentic farm on a field trip in conjunction with a unit on farming and agriculture. Students are familiar, at this point, with the more common  types of fruits and vegetables grown that are native to their area. They are able to recognize these fruits and vegetables by appearance, and they can identify them by name. Developmentally, the students are more capable of logical thinking in problem solving activities as long as they have concrete materials; their thought processes are more flexible and becoming better organized. The students have had prior practice with the following elements of the scientific method: observing, predicting, and recording.

General Objective:

To help develop students observational, prediction and recording skills.

Behavioral Objective:

After observing, weighing, and examining pumpkins, students will complete a pumpkin observation worksheet that requires them to predict and compare their predictions regarding at least three of the pumpkins¹ physical attributes.

Materials:

-Pumpkins of different sizes (one for each group of four students)
-Scales
-Knife
-Paper towels
-Paper plates
-Black markers
-A pumpkin observation worksheet for each student (See example below.)
-Overhead transparency of the pumpkin observation worksheet and overhead projector

Procedure:

[Note: Pumpkins--one for each group of four students--need to be obtained in advance for this lesson.]

1. The teacher will remind students of their trip to the farm, and ask students to think of some fruits and vegetables that are grown on a farm.  The teacher will write the following question on the board: "What is orange, grows from the ground, has seeds inside, and sometimes has a face carved on it?" (Students should answer, "a pumpkin")

2. The teacher asks: "What things can you tell me about pumpkins?" The teacher will create a semantic web on the board with the students¹ responses. (They're orange, Halloween, have seeds inside.)  The teacher will ask students for their opinions about whether or not pumpkins are full or empty . The teacher will then ask: "Are all pumpkins the same or different?" (Answers to this will probably vary).

3. The teacher will inform students that today they are going to have the opportunity to see what¹s inside a pumpkin and to find out if all pumpkins are the same--and if not, how they differ.

4. The teacher will inform students that today they will be scientists; they will be observing, predicting, and recording their findings. The teacher will remind the class of their previous science experiences in class by saying: "We are going to perform some of the same jobs on the pumpkin that we did with our lima beans."

5. Next, the teacher will explain to the students that they will be working like scientists and that they will be working in groups of three today and that they will be recording their observations on a special observation worksheet.

6. Before dividing the students into their groups, review the procedure they will need to follow once their groups are formed:

--Explain that each group be given a number. The group will then be given one pumpkin and a black marker for the group. Students in the group should select two people to collect materials for the group.

--One person in each group should then write the group number with the marker on the bottom of the pumpkin.

--A large model of the observation worksheet will then be used to explain the form--using overhead projection or the chalkboard. Indicating specific locations on the observation worksheet model, the teacher will tell students that their first job as scientists will be to carefully examine their pumpkins and then to draw a picture of what their pumpkin looks like in the "before" picture box. The teacher will then explain that the next step will be to answer the prediction questions on the worksheet. Finally, after each group has had an opportunity to examine and measure their pumpkin, recorded the actual weight, what they have found inside the pumpkin, and the number and color of seeds, the observation worksheet should be completed. To complete the worksheet, students will need to record what they actually have found and draw a picture of the pumpkin after it was cut open. They will then be told that they will find it interesting to compare what they have predicted with what they actually find and that they will have an opportunity to disucss the differences.

(The worksheet should be designed so that it includes space for the elements described. The student's name, a large space for a drawing of the pumpkin before it was cut open, a predictions list, including weight, number of seeds, color of seeds, and other predictions; a large space for a second picture after the pumpkin was cut open; and a second list corresponding to the predictions list for students to record what they actually found when the examined the contents and weight of the pumpkin.)

7. Ask for any questions about the group work and the observation worksheets. Clarify the directions as needed.

8. The teacher will then divide the class into groups of four and give each group a number. Students will be reminded to select two volunteers to distribute and collect materials for their group.

9. The teacher will give each group one pumpkin and a black marker and ask that the group number be written on the bottom of pumpkin.

10. Next, approximately five minutes will be allotted for free exploration. The teacher will distribure the pumpkin observation worksheets during free exploration.

11. After students have had time to write their predictions the teacher will ask one of the two materials volunteers from each group to come to the front of the room and pick up a paper towel and paper plate. The other materials volunteer from the group will be responsible for getting a scale from the back of the room.

12. Then, the groups will be encouraged to work independently while teacher walks from group to group offering assistance as needed and ensuring that students understand the task.

13. After approximately 20-30 minutes, the teacher will ask students to finish up the observation worksheets so that, as a class, they will be able to hear the findings from each group.

14. Each group will be asked to report their findings to the class. As reports are given, the teacher will record responses on the board. (Common differences are likely to be reported regarding weight, size of handles, and the number of seeds found in the pumpkins.)

15. The teacher will review differences in the groups' findings, and will ask students to elaborate on the factors that account for some of the differences.

16. The teacher will then engage the class in a discussion about why their predictions may have been different from their actual findings. The following questions will be raised:

--What did you think of when you predicted how many seeds were in the pumpkin? (Size will be suggested.)

--How was your prediction different from the actual number of seeds you found inside your
pumpkin?

--If students have found it easier to predict the weight than some other factors, ask: ³Why might the weight of the pumpkin be easier to predict than other factors?² (Because the size gives some idea about the weight.)

--What did you notice about the pumpkin during your observations that you hadn¹t noticed about them before? (Students may have noted that the pumpkin has lines separating in to different segments, that the handles seem to vary in shape and size, or that the colors are different.)

--What surprised you most about the inside of the pumpkins?

--Are all pumpkins the same or do they appear to be different from one another? (Students should say "different")

17. Volunteers will be asked to put scales away and dispose of garbage. Students will be instructed to put pumpkin remains in a brown paper bag that the teacher will circulate so that the teacher can put pumpkin remains in compost pile at home. The teacher will collect and wrap some seeds for distribution for students who are interested in drying seeds for planting at home.

18. Finally, the teacher will collect and evaluate the observation worksheets.