Using the principles of simple levers many simple but attractive and entertaining toys can be made.  One of the simples must be the ones you sometimes see that hang from a thin cord and have extending arms and legs when the lower cord is pulled.

When a lever has the pivot point in the centre with the effort applied to one side and a load moved on the other - then the lever is called a 'class one' lever. 

Usually class one levers require a large movement being made with only a small effort - the output is  movement through a small distance but with much greater force.  This is the sort of lever that could be used for moving a boulder in the garden.  However if it is used he other way round and only a small load is needing to be moved - the arms and legs of our model in this case - then a small input movement can produce a much larger output movement at the other end of the lever.