For a dramatic illustration of density check out this demonstration. It's simple to do, only requiring a bowling ball and some water.

In this experiment, you test whether two different bowling balls will float or sink, then determine the density of each of the balls to see if they are less than that of water.

Throughout the activities in this investigation, students may have wondered how a boat made out of steel, which is more dense than water, can float. This activity addresses that question. Students will see that changing the shape of an...