Students work in pairs. Partners take turns drawing a cube out of the bag without looking, making a mark on the appropriate strip of grid paper to record its color, replacing it, then drawing another cube, until 10 draws have been made. Students can repeat the activity several times. Together partners decide how to measure around the base of a geoblock with a piece of string.
Students use the display to compare and answer questions about the information they gathered.
Challenge students to organize the data by ordering the geoblocks according to the lengths around their bases. They take turns testing objects to see if they float or sink and re-sort the groups according to the results of their experiments. Students discuss other common attributes of each of the groups. Students discuss their strategies for making the estimates. Allow them to change their estimates during the discussion, if they desire.