Here in the U.S., we occasionally hear the term tweens applied to children from about 9 or 10 to perhaps 12 years old. It implies the childs attempt at adjusting from a childhood of carefree play with friends and toys to the more difficult teen age years and all that goes along with it.
Most common name for children, I suppose, is simply "kids"... but "my favorite tax deduction" isn't far behind...