Same weight, same volume?
3. Test predictions
Distribute four empty containers and a container holding 40g of mineral oil to each group. Then have the students test their predictions by filling the containers with a measured amount — 40 grams — of each of the other four earth materials (sand, water, organic soil, and gravel), which they will find at the weighing stations. Students may divide up the work.
As you circulate among the groups, check that they remember to allow for the weight of the empty container and its lid (approx. 26g). The total weight of the sample should be 40 grams plus the weight of the container.
Provide time for students to record their observations in their notebooks using labeled drawings [What is the volume of 40 grams of an earth material?].
Too much soil? Forty grams of organic soil may not fit into one container. Have additional empty containers available for students to use if they need them.
Once the containers have 40g of material, students can tap them a few times to settle the contents, but they should not compress the materials directly by pushing down on them. They should then place the materials in volume order, from least volume to most volume.
