## Friday, March 23, 2018

### Playing With Integers

Living in the northeast, my students get a lot of real life experience with negative numbers every winter.  Integers don't show up in our standards until grade 6, but my students get a fair amount of exposure to them much earlier than that through real life experiences with temperature.  Here is a problem I posed to my students earlier this week on the first day of spring.

I just snapped a picture of the outside temperature as it shows up in my car when I got home after school one night and then again the next morning as I was leaving.  We had quite a temperature swing and unseasonably cool weather for the first day of spring and many kids were talking about the weather that day.  I love when I get a chance to capitalize on their interest with a well timed math problem.  This problem led to some great discussions about addition strategies and integers in all the grade levels.  Many students used or thought about number lines and in the older grades we talked about writing equations to go with this type of problem.

My sixth graders will have a more formal unit on integers in about a month but in the meantime, I introduced a game to my 5/6 math group a few weeks ago that is giving them a lot more experience playing around with integers. It is a card game called Absolute Zero.  Each kid gets between 3 and 5 cards in their hand then draws and discards a card each time it is their turn.  The cards are positive and negative numbers and the goal of the game is to get zero.
 The current sum of this hand is 10.  On the next turn, if I draw a -3, I could discard the 7 and the sum of the hand would be zero and the round would end.
One particular group of kids has been playing this game every spare minute they can and really playing around with strategies for winning depending on if you have 3, 4 or 5 cards in your hand at a time.

Another group of kids has loved playing war with these cards.  They have been playing addition war at this point, but some of them are ready to start thinking about integer multiplication so very soon I will be showing them how to play the same game with multiplication.

 Kids have been integer addition war.
You can learn more about Absolute Zero, print record sheets and see some videos of the game in action over at their website.