Sunday, November 4, 2012

Pumpkin Math

To add to our discussion of seeds...and because Halloween was this past week...and to have some fun with math....we read the book How Many Seeds in a Pumpkin? by Margaret McNamara, with our guest reader, Zane Mingus (who had the day off from Fox Elementary in the wake of Hurricane Sandy):
The children in the book guesstimate the number of seeds they think will be inside of three pumpkins of different sizes, and then count the number of seeds by twos, fives, and tens.  We took a look at our medium-sized pumpkin and then took some estimates - anywhere from 500 to 103.  Then it was time to scoop out our pumpkin:

How many seeds could be in there???
 Picking seeds is messy work!

That night, the seeds were taken home, cleaned and roasted for our counting exercise. 
On Halloween morning, one group counted seeds by fives and another group counted by tens.
 We tried different sorting/grouping strategies.
 Counting by fives:

Counting by tens:


We met for math to discuss our counting strategies and our results.
We combined the totals from the tens group to the fives group to get the total number of seeds inside the pumpkin - and then we double counted the total number of seeds together as a class.
There were 403 seeds inside!  (F. came closest with her guess of 400!)

For some extra fun on Halloween, the students were encouraged to create their own
spooky Halloween math story problems.  Look on...if you dare!

T's pop-up problem:  There are 20 feet cooking in a pot.
If I fish out 18, how many do I have left?

Many of the children still face the challenge of the final question in a math story problem.
Once this story was presented, we talked about how to pose a question about addition
(how many more?) and questions about subtraction (how many left?).

1 comment:

  1. Owen and I loved looking at this together, thank you!
    Kara and Owen