The history of civilization is essentially the record of man's [and woman's] creative ability.
-- Osborn ( 1963, p. ix)
I spent a morning at a special summer program for "mentally gifted kids," the ones who score within the top one or two percent of all children in their age group on intelligence tests. Every morning, the 2nd- to 10th-graders gather in a small auditorium to contemplate a "thought for the day," work on a puzzle, plan activities, and grape about the usual things all kids gripe about. The puzzle for the day was "How can you take one away from 9 and get 10?" The kid sitting next to me whispered, "Do you know the answer?" After a few seconds thought, I gloated with a "Yes" response, pleased as punch that I could keep up with this elite group of short people.
Many hands shot up in response to the puzzle. The first child to answer was a tiny, redheaded girl, reminiscent of Charlie Brown's heartthrob. "It's easy," she said as she walked confidently to the chalkboard. "If you take away a negative one, the effect will be the same as addition." As she spoke, she wrote the following on the board:
9 - (-1) = 9 + 1 = 10
I was amazed. Why hadn't I thought of that? A second hand went up and a young boy on the verge of adolescence explained another answer: "In Roman numerals, nine is written 'IX,' so if you take 'I' (one) away, you'll end up with 'X,' the Roman numeral for 10."
Another child responded with a sheepish grin, saying that, "This is a little silly, but, if you write '9' and take the one, or vertical line, away and place it in front of the changed number, you'll have '10." I don't know why this was a silly answer--it was the one I had been thinking of.
Still more hands were up, anxious to demonstrate more ways to answer the puzzle. One child wrote out the word "NINE," then erased the second letter (the i that looked like a one), which left her with a "N NE." If you count the number of straight lines left in these letters, there are 10 (three in each "N" and four in the "E").
Actually there were even more answers, but I lost track as I sat with my mouth gaping open, trying to follow each explanation. Their usual summer curriculum included activities