Wednesday, January 20, 2010

Do you Sudoku?

I do. And Charlotte does too, after a fashion.
Monday afternoon, while her brother slept, and Charlotte was working on a craft project, I sat down to do the Sudoku from the morning paper.  I like these little puzzles and kept a calendar of them at work this last year.  Once you learn the pattern of solving them, they go pretty fast (unless you get ahead of yourself and mix up a few numbers early on, ahem).  Charlotte was immediately interested in what I was doing.
I showed her how the puzzle worked, and explained that you can’t repeat a number in any row, column, or small box.  She wanted to try.  She was serious.  So I though I’d start her off with a fairly simple one.  3x3, not 9x9.  I grabbed some paper, drew up a key, filled in about half the boxes on a grid, and handed it over.  I thought I’d have a couple of minutes to work out a few more digits in my own puzzle.  Um, no.  She finished it before I remembered whether I was already checking rows or columns.  She demanded more.  I made a second 3x3 puzzle.  Again, finished in the first try, about 60 seconds flat (she’s not very fast at handwriting).
So I sat down to make a 4x4 puzzle.  These are a tad harder to hand-generate, btw.  But once I had a working key, I realized that if you divide the 4x4 grid into 4 2x2 boxes, then the numbers don’t repeat within the boxes.  Cool.  Like a 9x9 (And I suppose it would also work out neatly in a 16x16 grid…hex-Sudoku here I come…).
That puzzle took her more time, and she actually had to do some re-factoring and re-thinking, and we erased the entire grid once for her to start fresh.  But she solved it, with the exception of one solitary number.  Then she asked for more.  At that point, I deferred her to later, since she was also getting a little too frustrated (and refused to switch the one incorrect number, even though she knew what the right answer was). 
Charlotte is, perhaps unsurprisingly, fast at picking up on mathematical and logical problems.  She is all-around bright, really, though handwriting is hard for her (also unsurprisingly, as anyone who’s ever seen my handwriting could agree).  But I am always making up numbers-type problems for her at home—demonstrating slicing a pizza and asking her to figure out how many slices we can all have, or how many we’d get if we sliced more times, how many cookies are left if everyone eats one, If we have 3 rows with 4 cupcakes each, how many are there.  Math and cooking go together, though she’s becoming more and more interested in problems involving money right now…
This is one area that I think her pre-school all but skipped.  Their idea of math was to teach the kids to count to 20. But in Kindergarten, she’s getting a well-constructed study of math and logic designed to challenge kids, in a school that prides itself on being “academically rigorous”.  And she’s keeping up and helping out her friends.
And to think, according to the state of Missouri, Charlotte is not yet ready for school.  Huh.  Guess I need to write a little Sudoku generator tool.


RAK said...

I know your point is about Char, but anyway... I gave up on regular 9x9 sudoku because I finished them too quickly. My current challenge is the 7x7 KenKen puzzles in the New York Times Magazine. I've managed a few of them, but they're pretty tough!


Kristi said...

I just discovered the KenKen puzzles
too, Becky. Picked up a "page a day" calendar of them for work. I still have a stack of sudoukos from last year, and kakuros from the year before (I'm not there every day and don't always get time to finish them). The KenKen calendar so far is only up to 5x5 grids, but they get bigger as the year goes on.

I think Char will need a bit more practice with written math problems before she can do the KenKens (what, 2nd grade at this rate?) LOL.