This ITP has been remade so that it will work in modern browsers. It will remain free to use.

This ITP allows you to add different masses to or from a scale pan. You can add masses of 1, 2, 5, 10, 50, 100 and 500 units. The pointer or hand shows the total mass. This can be hidden to promote children’s prediction skills. The maximum value of the circular scale can be changed together with the size of the interval. A digital readout can also be hidden or displayed. A red marker can be used to keep a track of previous values and to set target quantities.
The ITP can be used to support children’s calculation strategies. Using different scales can support their estimation skills in reading circular scales and solve problems set in the context of mass.

For more measuring and time resources click here.