SeeSawTask 58 ... Years 2  7SummaryStudents create a seesaw and explore balancing objects of different masses. The challenge is to make statements and draw diagrams that summarise the experience. For example:Light things can balance heavy things if the heavy things move in and the light things move out. 
Materials
Content

IcebergA task is the tip of a learning iceberg. There is always more to a task than is recorded on the card. 
The task is quite an openended exploration. Who knows what will be discovered? There is a relationship behind what happens and it is expressed mathematically as M = Fd, where M = Moment (or Torque), F = Force at a distance d from the fulcrum (or balance point). The force in this case is downward and described as the weight of the object. Balancing happens when the Moment of one object is equal to the Moment of the other. ExampleNo one is expecting Year 2 students to express their understanding in this way, but an explanation such as: Light things can balance heavy things if the heavy things move in and the light things move out.displays understanding of the essence of the system. It is also the principle behind the Number Equaliser in many classrooms  a balance on which students hang masses to explore equations. The objective of the task is to encourage students to explain  orally, then in written word and picture  what they have discovered. Questions which might encourage this are:

Whole Class InvestigationTasks are an invitation for two students to work like a mathematician. Tasks can also be modified to become whole class investigations which model how a mathematician works. 
It only takes each pair of students to have a ruler and the teacher to have a variety of objects for this activity to be a whole class investigation. But it need not be that all students work on it at the same time. It works well in an activity corner too. You might be surprised at the outcome. A teacher at one remote Aboriginal school was. The playground had a real seesaw. After this task was used in class she found students of all ages gathered around it balancing younger students against older ones. At this stage, SeeSaw does not have a matching lesson on Maths300. 
Is it in Maths With Attitude?Maths With Attitude is a set of handson learning kits available from Years 310 which structure the use of tasks and whole class investigations into a week by week planner. 
The SeeSaw task is an integral part of:
