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This is a super easy fall math activity for kids. All you need is one or more pumpkins, some string, a pair of scissors, and a tape measure. With these tools, your kids will be ready to estimate the circumference of a pumpkin and learn a few math skills as they do!
Note: You’ll find more fall learning resources on my Fall Activities for Kids page.
Circumference is the distance around an object. Circumference is also a great geometry vocabulary word to introduce to kids. My kids and I talked about what the circumference of a pumpkin was, and then we set about measuring it.
During the time we did this activity, my son was going through a period where he was fascinated by measuring things and loved any opportunity to use the measuring tape. So we wrapped some string around the horizontal circumference of the pumpkin and cut the string to size.
Then we measured the string with a tape measure. QBoy was so proud of his ability to read the numbers on the measuring tape and tell us how big the circumference was.
This is such an easy fall math activity, but despite its simplicity it still gives kids the opportunity to practice plenty of great math skills. You can also use a flexible, cloth measuring tape to eliminate the need to cut a string to size.
Depending on the ages and skills of the kids you are working with, there are several variations on this activity you might try:
- Measure several pumpkins and then place the strings for each pumpkin’s measurement in order from smallest to largest. Measure the differences between the strings.
- Have your kids estimate the circumference before measuring it, either by guessing the number of inches or centimeters or by cutting a string to what they believe the correct size will be.
- Measure both the circumference (distance around) and the diameter (distance across) of the pumpkin and compare the two measurements, particularly their ratio. Do the same for several pumpkins and see if the ratio between circumference and diameter is the same for all the pumpkins.
- Measure the circumference of several pumpkins and then calculate the average (mean) circumference of all the pumpkins.
Looking for more Halloween projects that incorporate Science, Technology, Engineering, Art, and Math (STEAM)? Then you’ll love STEAM Kids Halloween.
This e-book includes 50+ pages of spooky fun STEAM activities that will wow the boredom right out of kids!
More pumpkin resources for kids
More pumpkin posts from Gift of Curiosity:
- Describe a pumpkin using all 5 senses
- Pumpkin decomposition demonstration
- Pumpkin decomposition experiment
- Pumpkin arts and crafts
- Pumpkin do-a-dot printables
- Printable pumpkin outlines