Thursday, October 3, 2013

Make a 10!

Understanding bonds of ten is a vital component of mental math.  Students are encouraged to use a "10-frame" to add and subtract (eventually this is all done through mental images).  Here is a sample 10 frame:

The 10-frame can be filled with counters, coins, erasers, small toys, and the list goes on.  

Steps to solving a problem using a 10-frame: (8 + 5)
1.  Fill the 10-frame with counters matching the largest number

2.  Use the second addend to fill the ten frame ("make a ten").  The filled 10-frame is the ten.  The left over counters will be the number in the ones place.  

I use 10-frames as part of my math stations.  However, I use egg cartons (with 2 spots cut out) as the 10-frame.  It adds a little more interest :-)


From there, the students roll two dice to get the two addends and fill the 10-frame as mentioned above. Last, they have to use "math talk" to describe the problem.  An example is written on an index card with the station: ____ + ____ = ___ ten and ___ ones.  This makes _____.

I don't know about you, but it is pretty cool to think about how people think! "Making a ten" is totally how my brain operates... didn't realize that until I started teaching mental math!


3 comments:

  1. So help this momma out... :) Your example... am I following you correctly that the answer is 13? 10 and 3 ones = 13?

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  2. You're right Shonna! Here's another example with 8 + 7 (This works if you don't have it memorized :-). First you would "make a ten" with the 8 by adding 2 (from the 7). Then you're left with 10 + 5 which is much easier to add. For bigger numbers it would work like this: 27 + 14. First add 3 from the 14 to turn 27 into 30. Then you're left with 30 + 11.

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  3. That is how I do mental math, too!

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