Roger Jackson, age 11, of Ottawa, Ont., Canada, for his question:

What makes a boomerang come back?

The boomerang belongs by right to the natives of Australia. It was invented by these simple people who learned the tricky skills of using it. An Australian native may throw a boomerang and make it return to his feet, but from your hands the same boomerang might not return. It might refuse to do any of the tricks you want it to do.

The surface and the angle of a wooden boomerang are designed to work with currents of moving air. The amazing weapon must be shaped perfectly in order to perform its tricks. It must be thrown by someone who knows the exact strength and flick of the wrist in order to use it. And this skill takes endless patience and practice. In order to make a boomerang come back, a person must begin practicing these skills at a very early age.