## Tuesday, 28 January 2014

### Mental Math

In the month of January during our daily calendar time, we have been working on our mental math skills.  The smart board number generator helps us  make random two digit numbers that we need to find a way to add or subtract in our heads!We were pretty rusty at this skill at the beginning of the month but you should see us now!

We give a thumbs up to our teacher when we have the answer in our head.  This teaching strategy comes from the book Number Talks that our school's teachers did a book study with last year.  Then we list all the answers that we came up with and decide which one is right.  We can learn so much from our mistakes!  We notice when everyone had the same number of units and the tens number is one different.

The interesting part is hearing how everyone came up with their answer. Some people do the tens first, then the units.  Some people add up when they subtract.  Some people, like our teacher, stack the numbers in their heads and use carrying and borrowing. She went to school in the 1970's and that was what she learned.  We are teaching her new ways to think about numbers!