This document outlines a multi-grade math activity involving pumpkins that teaches concepts such as ratios, circumference, scatterplots, and linear functions. It includes step-by-step procedures for measuring and graphing the data, culminating in understanding the relationship between circumference and diameter, represented by the ratio π. An optional component suggests celebrating the activity with pumpkin pie for the students.

1. A Multi-Grade Math Activity

2. 
 Here is a hands-on activity that allows students to
explore a number of concepts, depending on the
grade you teach:
 Ratios
 Circumference and diameter
 Scatterplots
 Linear Functions
 Slope
Overview

3. 
 If your class is planning a trip to the pumpkin patch,
gather as many different size pumpkins.
 Measuring tape
 Two-column chart for gathering data
 Larger poster for displaying data graph
 Optional: Graphing calculator or graphing software
Materials

4. 
Procedure
Step 1
Have students measure
the diameter of the
pumpkin. Have them find
the widest length across
the pumpkin.

5. 
Procedure
Step 2
Have students measure
the circumference of the
pumpkin. Have them find
the widest length around
the pumpkin.

6. 
Procedure
Step 3
Have students combine
their measurements into
one data table. Make sure
they enter the correct data
in the appropriate column.
Make sure their
measurements are in the
same units.
Diameter (in.) Circumference (in.)

7. 
Procedure
Step 4
Graph the data as a
scatterplot. If your class
hasn’t covered this topic
yet, simply graph the data
for the students or use a
graphing calculator or
spreadsheet. Choose an
appropriate scale.

8. 
Procedure
Step 5
Try to find the line of best
fit either visually or
quantitatively. Ask
students to interpret what
the linear graph means.

9. 
Conclusion
The ratio of
Circumference to
Diameter is π, which also
happens to be the slope of
this line:
C = πd
The secret to the Pumpkin
π is in the ratio.

10. 
Optional
Complete the activity with
some real pumpkin pie for
students to share!