For this activity you need a pair of balance scales, a  number of cubes, small bricks, marbles or coins and some small toys. The idea is to weigh the small toys by using the bricks/marbles. Pick up a small toy, hold it and make an estimate, or guess, as to how many cubes will balance it on the scales. Write down the guess, then place the toy on one side of the scales. Add the cubes to the other side until they are level which is the point when the weight (mass) balance each other. Record the total number of cubes on the chart provided. Measuring weight (2)