The Power of Pennies, or Don't You Want to End Up Rich? Math Genius Challenge Number 2

     It's always fun to dream about getting rich.  Most of my dreams involve buying a winning lottery ticket...sigh...but that's most likely NOT going to happen.  Not to me, and not to you!  So, all you math geniuses, I thought today we could look at the power of pennies!

    One of my favorite questions of all time is:  would you rather have $1,000,000 or would you rather get a penny the first day, that doubles everyday thereafter, for a month?  Most people choose the $1,000,000.  I did too, until I did the math.  It's a simple lesson - just complete this table - and then...you tell me which you'd rather have!  Make sure you include what day made you change your mind!  (And then start saving those pennies!!!!)

DAY #                                 AMOUNT                         TOTAL
  1                                             $.01                             $.01
  2                                             $.02                             $.03
  3                                             $.04                             $.07
  4                                             $.08                             $.15
  5                                             $.16                             $.31

You continue this pattern until Day 31.   :-)

Good luck!

Susan Curtis

Math Genius Challenge Number 1

    Ever know that something is wrong, but just have a hard time explaining why?  This challenge is for you!  I was watching movie clips about math and ran across several old clips of Abbott and Costello (google them if you've never heard of them!) explaining how to divide 28 by 7.  I knew the math was wrong, but I didn't stop and think, "how would I explain why this is wrong" before I showed it to my summer school students.  MAJOR MISTAKE!  :-)  Having students who struggled with division watch it just confused them further...and then my explanation only continued the madness!  Disaster of a lesson!
     But...that lesson did bring home the point that being able to clearly explain WHY something is incorrect is important.  (Not to mention the fact that I was reminded to think through everything before I teach it! LOL!)
     So, your assignment today, math geniuses, is to watch the Abbott and Costello movie clip, and explain the incorrect thinking in it.  1,000,000 points to the best explanation.  (And no, I have no idea what you can use the points for, but it sure is a lot of points, isn't it? :-) )  Post your explanation in a comment by August 23, 2010 for a chance at the million points.  Good luck!


Abbott and Costello 28 divided by 7 is 13
Abbott and Costello 7 x 13 = 28


Susan Curtis
     

Welcome!

     Hello!  Welcome to a new school year!  I'm a 5th grade math teacher who is trying something new - blogging about math - the teaching of it, the learning of it, the fun of it, and the not-so-fun of it.  This blog will contain both my thinking and that of my students.  Others are more than welcome to chime in, too!  
   I'm looking forward to hearing what others think about math.  Check out other posts for challenges for all the math geniuses out there!


Susan Curtis