Young children learn by doing, and “active play” includes both structured and unstructured activities. If there’s been a snowfall and children play in the yard piling up the soft snow and rolling down the pile, that’s unstructured play. Later, when the weather warms a bit, they find that the snow has become sticky and they can create snowmen. This is also unstructured. 
 
Structured play is when an adult creates a stimulating environment and children are encouraged to explore. But what can be defined as “structured” differs depending on the age of the child. 
 
For more information check out Mr. M. Haliburton's Web Site!