Four Strikes and You're Out

March 14, 2011

This week we are playing Four Strikes and You're Out.  It's a game I adapted from one found on the Scholastic.com website created by Marilyn Burns.

To Play:

2-3 players can play this game.  One player is the "teacher" who writes a 2-digit plus 2-digit addition problem on a sticky note.  The "teacher" must also write the sum before beginning the game.  For example, the child might write "34 + 19 = 53" on the sticky.  The "teacher" does not allow the others to see the post-it.  She writes a "hangman" style problem in her math journal:
        __ __ + __ __ = __ __

Then she lists our 10 digits below the problem.

1  2  3  4  5  6  7  8  9  0

Now the game begins.  The player (if it is group of 3, the players take turns) guesses a number.  The "teacher" checks the sticky.  If the digit appears in the problem, the teacher writes it in the blanks where it appears before crossing it out of the digit list.  If the digit appears more than once, the child writes it in every correct blank. 
   
For example, in our sample problem, if the player guessed 3, the teacher would complete the journal page in this way:

        3 __ + __ __ = __ 3

1   2   X   4  5  6  7  8  9  0

If the player chose a digit that does not appear in the number sentence, then the teacher crosses out the digit and records "Strike 1." 

If the player solves the number sentence before getting 4 strikes, then he wins.  If he gets 4 strikes, then the "teacher" wins.  When the game is over, the sticky note is attached to the journal page before the children trade positions and play again.

To introduce this game, I played against the class on the Smartboard (or whiteboard).


Writing About Math
Journal Prompt:
Imagine you are playing Four Strikes and you see this:

__ 7 + 2 7 = 5  __

What is your strategy?




If your student needs hints:
What digit would you guess next?
Which fact strategies would you use:  ones, twos, doubles, near doubles, nines, tens.
Describe your strategy for guessing the missing tens digit?

From the student journals:

First I would see 7 + 7 = 14, so I would have to regroup the one.  Then I would have to add one to ___ but the blank would have to be 2 because if you add the one to it, it has to finish the number sentence 3 + 2 = 5.

So...27 + 27 = 54  (student 20)

What I would do is look at the tens.  Think about what plus what equals 5.  What??  I know that 3 + 2 = 5, so it has to be a 3 in the tens place.  

So, we move on to the ones.  7 + 7 =14.  So the ten now has to be a 2 and so the problem is 27 + 27 = 54.  (student 21)

So, I know that this number sentence is regrouping.  Because it's 7 + 7 =14.  So it can't be 37 + 27 because then the answer is 64.  However, 27 + 27 works.  It's because 7 + 7 = 14, and 1 + 2 + 2 =5.  The number sentence is 27 + 27 = 54.  (student 4)