More or Less?

Prepare a display that challenges viewers to guess the mass or volume of different objects or samples of matter. You may use the following suggestions or develop some ideas of your own.

1. Display several objects of approximately the same size, but made of different materials, such as clay, wood, plastic foam, and metal. You may wish to paint all the objects the same color, so that viewers can't tell what they're made of. Add numbers to each object, and challenge viewers to rank the objects by mass, from greatest to smallest, simply by lifting each object once.
2. Display objects of the same shape, but different sizes and masses. At least one of the smaller objects should have more mass than a larger object. Number the objects and challenge viewers to rank the objects by mass simply by looking at them.
3. Display 3 or 4 containers of different shapes, each containing the same amount of liquid. For example, you might use a tall, thin container, a short, round container, and a square container. Ask viewers to rank the volumes of liquid, from most to least.