How do we measure liquids?

Friday I brought a container of water to math group and asked the students how we could measure a liquid. One student suggested that we could measure the temperature with a thermometer (calling up a S'math lesson we did earlier this school year.) Another said we could find out how much it weighed. Then someone pointed out it would be hard to find out because if we weighed it on a scale, we would also be weighing the container it was in. We discussed how to get around that problem. Then someone suggested measuring liquid with a measuring cup. I brought out some measuring cups and liters, and we looked at those.

Then I brought out a tall, thin glass and a short, fat glass. I asked which they thought would hold the most water. One student said he thought they would hold the same amount. The others were divided between thinking the tall glass and the wide glass would hold the most. When we carried out the experiment, it turned out they each held exactly 1 cup.

As we moved on the Math Choice time, some students chose to experiment some more with the water and the different containers.

Measurement Explorations

We have been working on finding items in the classroom that are about as long as the white and orange cuisinaire rods. Once students found 5 items for each, we learned that the white rod is one centimeter long and the orange rod is 10 centimeters or 1 decimeter long. Another day we did the same activity using inch cubes. After these explorations, students had to measure some things at home with rulers or yardsticks for homework. Where possible they were to measure in English and metric units. As we shared the results of their measurements last Friday, we developed a clear sense of the relationship between an inch and a centimeter.

This activity was drawn from Marilyn Burn's work.