Pumpkins aren't just for Halloween. In fact, this spherical orange squash lends itself quite nicely to several math activities that will give fifth graders hands-on experience working with numbers. The pumpkin even gets a few bonus points because it can give teachers and students the opportunity to get a little messy as they hone their math skills together.
Count the Seeds
The number of seeds contained within any individual pumpkin will vary from pumpkin to pumpkin. The only way to know how many seeds a pumpkin contains is to pull them out and start counting. Begin by supplying small, medium and large pumpkins to the students. One pumpkin for each three or four students is sufficient, as it will enable students to work in groups to lighten the load and encourage collaborative questioning and discussion. To prepare for this activity, cut off the tops of each pumpkin, while also ensuring that knives are not available for students. Supply each group with scoops and bowls, and encourage them to get to work, scooping out pumpkin guts. Allow the students to decide on a strategy to use while counting the pumpkins. For instance, they may choose to tally the seeds or to group them into easily recognizable amounts. Once the groups have made their final counts, open up the class for discussion so the students can share their findings, comparing and contrasting their counts.
"Fair Share" is a division activity that students can complete using small, hollowed-out pie pumpkins, gourds, or paper pumpkins. Divide the class into groups of three or four students and give each group a different number of pumpkins or gourds. Give each group the same number of pumpkin seeds. The number you give should be evenly divisible by each number of pumpkins possessed by the groups. Ask the students to use the pumpkins to figure out how many seeds each pumpkin should receive so each group has its fair share. Once each group finishes this task, ask them to write the division number sentence that fits their group. For instance, if the group has four pumpkins and 80 seeds, their number sentence would read 80/4=20. The group should then determine what fraction of the total amount of seeds one pumpkin's contents represents.
Pumpkins offer an opportunity to introduce circumference and to practice converting measurements into different standard measurement units. Provide a measuring tape and a pumpkin to each pair of students. Have the students work together to find the circumference of their pumpkins, first in centimeters, around the largest part of the pumpkin. The students should then work together to convert the centimeters to inches, and then inches to feet. As the students work, they should record their data. A teacher-made decorative data sheet, along with their pumpkins, can provide an appealing and informative accompaniment to work displays.
Graphing Pumpkin Weight
The class will need at least one weight scale, in addition to several pumpkins, for this activity. Before the activity, mark each pumpkin with a letter or number, and have students create double T charts with each of these letters or numbers printed down the left-hand side, and the words "estimate" and "actual" printed at the top. Begin the activity by asking inviting students to lift each pumpkin and estimate how much it weighs. As they work, they should write down their estimates on their T charts. After the students have taken all their estimates, use the scale to measure the weight of each pumpkins. The students should also record the actual measurements on their charts, as well. Finally, ask the students to use a strategy that will allow them to quickly see how their estimates compare with actual weights.