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Pumpkin Math




  • Arithmetic
  • Geometry
  • Measurement
  • Process Skills



Brief Description

Students estimate the weight and circumference of three pumpkins, predict the relationship of pumpkin size to number of ribs and seeds, and then test their predictions.


Students will

  • estimate pumpkin weight and circumference;
  • weigh and measure pumpkins;
  • compare weight and circumference; size and number of ribs;
  • predict number of seeds based on pumpkin size;
  • use charts and graphs to record their predictions and results.


math, Halloween, estimation, prediction, probability, measurement,

Materials Needed

  • three pumpkins of different sizes
  • a scale
  • a tape measure
  • carving tools (for the teacher)
  • three bowls (for pumpkin seeds)
  • paper towels
  • a large sheet of graph paper taped to a bulletin board or easel (optional)

Lesson Plan

Display for students three pumpkins of different sizes. Pass the pumpkins around the room. Invite students to hold each pumpkin and estimate its weight. Have students record their estimations.

Weigh the three pumpkins. Ask: How close are the actual weights of the pumpkins to your estimations? Encourage students to create a chart to show that comparison.

Measure the circumference of the three pumpkins. Ask: Does the heaviest pumpkin have the largest circumference? Help students compare the pumpkins by weight and circumference.

Encourage students to find the relationship between the size of each pumpkin and the number of ribs it has. Ask: How can that relationship be expressed?

Invite students to predict how many seeds each pumpkin contains, and have them record their predictions. Ask: Which pumpkin do you think will have the most seeds?

Arrange students into three groups. Cut the tops off the pumpkins and give one pumpkin to each group of students. Have students in each group remove the pulp from their pumpkin, count the seeds, and record the results. Have one member of each group report its results to the class. Ask: How close to the actual number of seeds was your prediction -- for the smallest pumpkin? for the largest pumpkin? for the middle-sized pumpkin? Award a small price to the three students whose predictions are closest.

Extension Activity: Encourage students to weigh and measure pumpkins at home, record the results, and record the results on a class chart of pumpkin weights and measurements. Ask: What conclusions can you draw from the chart about the relationship between weight and circumference?


Assess students based on their participation in the activity and the reasonableness of their predictions and estimations.

Lesson Plan Source

Submitted By

Gary Hopkins

Education World®
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Last updated 9/30/2016