I explained to my children and explain to my grandchildren that electricity and gasoline cost money. Kids as young as four or five can get the idea that the more money that is spent on electricity the less there is to spend on getting them stuff that they need or want. Sometimes it is hard to do this in a very gentle way, but patience pays.

A child who is wasteful at age five is likely to be a wastrel at age fifty-five. And definitely, if not by eight, then too late.

My own parents drilled a fanatical frugality into me from as early an age as I can remember--about three. I think one reason my wife left me was because of my strict habits of conservation and thrift.

BTW, it is tough to avoid a "holier than though" attitude as a stingy old man; I find that firmness, gentleness, and good humor help.