Measuring Mass

Show students a small, unopened spice jar with the mass in grams of the contents printed on the label. Pose the problem to the students.

Challenge the students to devise an effective strategy for determining the mass of a container without opening the jar. Have them create a plan with a partner. They can find the mass of a jar with the spice and then subtract the mass of the spice (listed on the jar label) from the total. Or, they can put the spice jar in one pan and then put masses to equal the contents noted on the label in the second pan. Then they count as masses are added to make the pans balanced.