We recently bought a very large bean bag chair that was a lightning deal on Amazon. Instead of the traditional bean bag filling, it has little chunks of memory foam in it. The kids love to curl up in it to read, which was the main reason that we purchased it. I thought that one child at a time would sit in it to read, but they have enjoyed piling 3 or 4 of them in it.
Since it was memory foam, it came compressed in a box. The directions said that it would take 7 to 10 days for it to reach its full size, but I fluffed it vigorously and it reached full size by the next day.
One of the kids commented that the chair was “twice as big as the box that it came in.” That sounded like a math problem to me, so we got to work. I explained that volume is measured in cubic inches and it is really saying how many 1 inch cubes would fit inside the object. Then the boys measured the box and the chair. Ruth recorded the numbers on the whiteboard. I added some diagrams and gave them the formulas that they would need. Then Elijah and Ruth completed all of the calculations on the board. I helped out a few times when they forgot what to do or made a small mistake, but they really did the work themselves.
We found that the box had a volume of 8,209 cubic inches, and the chair had a volume of 45,216 cubic inches. The chair has a volume five and a half times bigger than the box!
Shortly after we finished this activity, we were eating dinner and discussion the size difference in the chair and box. Ruth glanced up at the U.S. map that hangs by our table and said, “It is like Pennsylvania and New Jersey.” So I looked it up. Keep in mind that the volume of the box and chair were 8,209 cubic inches and 45,216 cubic inches. The areas of New Jersey and Pennsylvania are 8,729 sq miles and 46,055 sq miles. So PA is 5.28 times bigger than NJ. Wow that is excellent estimating!
I love when learning happens like this. Volume was not just some idea on a math worksheet, it was the means to answer a real life question. Yes, Elijah practices 2 digit multiplication in his math curriculum, but this was an opportunity to use his skills for a purpose. Isaiah had just been learning about measurement in his math book, and we had a reason to actually measure something.
The kids tend to just pile on so that the chair squishes flat, but if you sit in the middle, it conforms around you in more of a chair-like shape.
Look for those opportunities in life to respond to your children’s questions in a way that they can learn something new or practice the concepts that they have already learned.
If you are interested in one of these cool Fuf chairs, here are some links to different sizes (ours is the king):
P.S. I am sitting in the chair right now as I write this post. It is very comfortable. (I only link to products that I like.)