At a recent session in Wainwright, one of the participants, Mary Frank, showed me this demo. It’s similar to Dan Meyer’s Popcorn Picker, but I really like the payoff in Act III. Presented in Dan’s three act format, here’s the materials.
Act I – Video
Act II – Information
Have the students make predictions about whether the wider cylinder will overflow, fill right up, or have space left in it. If they want to run calculations, the tubes are simply 8.5 x 11 pieces of overhead paper. One is rolled vertically, and the other is rolled horizontally.
Act III – The Answer
Sequels
- How tall would the skinnier cylinder have to be to completely fill the wider one?
- By what factor are the volumes different? Why?
Awesome! For some reason the videos didn’t work for me every time… but the lead up to the end of act 1 is really well done! Thanks for sharing this
Love this video because of how well it is set up. Simple, yet effective. I think that students will easily ask the questions we are hoping for and they will remember what happened in the experiment. I also believe that students will remember the bid idea that the closer a 3D object is to a cube or sphere, the more volume it will have.
[...] The first approach most teams take is to calculate the volume of each cylinder. They’ll ask for (or google!) formulas. Even after determining the volume of each cylinder, many will remain unconvinced. Prompted with “How might young children solve this?” teachers will fill each cylinder with manipulatives available at their tables and compare the results, similar to the third act of Dan Meyer’s Popcorn Picker or John Scammell’s Surface Area vs. Volume. [...]