Today, we ask how many points to take off. The University of Houston's College of Engineering presents this series about the machines that make our civilization run, and the people whose ingenuity created them.

The 1996 Olympic Games have been driving me nuts. If I have to watch one more little girl break down and cry because she bounced when she landed, I'll switch channels to professional wrestling! I just watched a young man leave the hard floor and do three somersaults in midair. It was a violation of physics that boggles the mind. But when he finally fell from the sky, he took one backward step. That single glitch blew him out of competition.

This is no longer about real excellence. It's about the far drearier business of tedious perfection. The only way you can be perfect is to be cautious and conservative. I call what I'm watching, the Points-Off mentality. You start off with a score of 10 and then work your way down. I guess if you do nothing, you'll stay a perfect 10 forever.

Some Olympic events are untroubled by Points-Off thinking. When you race, you race against the clock. When you high-jump or long-jump, you're out to beat gravity any way you can. And that process can lead to invention. At some point a high jumper thought of pitching his body over the bar backward and landing on his back. When that happened, a whole new world opened up to athletes.

But gymnasts, divers, and most ice-skaters are dedicated to being perfect. Children who live to please adults by being perfect suffer whether they're athletes or not. I worry far less about beating up young bodies than I do about beating up young psyches.

Points-Off thinking isn't limited to the Olympics. We teachers are painfully aware that the graduate who goes on to greatness was often a C student. We too do a lot of Points-Off grading. Yet how can anyone be both a risk-taker and a straight-A student?

If the purpose of grading Olympic athletes is to identify a champion, the purpose of school grades is to drive learning. Very different objectives but Points-Off thinking undermines them both! Any teacher worthy of the name likes to see students who don't care about grades or any other rewards that come from outside. Good teaching means fostering learning that satisfies a craving inside the student. It means helping students to find that craving.

But that's so hard to do. It's difficult the way trying to grade a gymnast is. It's so much harder than deducting points for moving a leg when you land on the mat. Points-Off is the easy way -- to raise a child, to rank a research proposal, to tell right from wrong. Points-Off is worse than just avoiding the real content of human accomplishment. It's the way we tell children that action simply gives them a way -- to slip out of first place.

I'm John Lienhard, at the University of Houston, where we're interested in the way inventive minds work.

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