[Dump and Chase]

I would think this would have more to do with balance and skating ability then it does with age.

Once they can keep their balance through the shot without flailing or falling off their skates they are ready to learn how to do it.

There were a couple of 6 year olds in my sons 3 on 3 league who could shoot a balanced slap shot and could put it any where in the net. I don't think the average minor hockey player wouldn't be ready for this until 8 or 9 years old.