```Date: Jan 20, 2013 2:31 PM
Author: Robert Hansen
Subject: Re: To K-12 teachers here: Another enjoyable post from Dan Meyer

On Jan 20, 2013, at 11:51 AM, Joe Niederberger <niederberger@comcast.net> wrote:> - ---------------------------------> Because, if> - - -- DEAN - NED = A, then> - - -- DEAN - NED should not = D unless you really wish to foncuse those pre-algebra kids!> and> - - -- ARIEAL - BLAIRE = B is also likely to foncuse.> - ---------------------------------> > That's why I said that I'd like to see their scratch paper. Kids have different talents at organizing their scratch paper work (and double checking thereof). Its very related to algorithm building, and that old fashioned view of math that insists that the correct answer shows up at the end.> > Cheers> Joe NThe original name was actually "ARIEL" not "ARIEAL".On a puzzle like this your interest is in checking the work? To me, this isn't a very good problem for "checking the work" because the only significant detail is "seeing the trick". I don't know how the teacher framed this problem when they presented it to the class. If the teacher gave away the trick and after that only 2 students got it then I am indeed very saddened. If the teacher didn't give away the trick and only 2 students got it then I would understand, although, I wish we could do better.99% of this puzzle (and all puzzles) is "seeing the trick". I don't think that has anything to do with organization and double checking. In fact, in order to "see" solutions to puzzles, organization is probably the last thing you want in your mind. It won't allow you to "see".A puzzle can be defined as a problem that is alleged to have a solution but that solution is not obvious. However "not obvious" can mean...1. There is no obvious solution.2. There is an obvious solution, but obviously not the one intended, because it would be impractical.There isn't any algorithm I am aware of to find non obvious solutions. You must rely on "seeing in the dark" which involves instincts not generally used when "seeing in the light". Indeed, you must even suppress your "seeing in the light" instincts, as you do when walking through a dark room, or else they will fool you with "not seeing" and you will run into something.Bob Hansen
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