And in this case we have a whistle! Let's try to make it with your own hands without using expensive materials and a complex tool.
To begin with, looking for a piece of suitable round blank, about 20mm in diameter. Drill it along and through the drill on 10mm.
At one end, we make a drink across, until the middle of the diameter. And a sharp knife, neatly, cut off the wood towards the drift, at an angle of 35-45 degrees.
From the end without drinks, we do the plug, it is necessary that it would be tightly and did not let the air.
On the other hand, the whistle also put the plug, which is cutting off 2 / 5th diameter .. To go through air.
The whistle is ready, experimenting with the size of the holes and the long whistle you can achieve the desired tonality.
And when they have a hand, you will be able to please your children and children familiar with such whistles.