I know I am not alone in when I write that math has never been one of my favorite subjects (except for algebra, which I loved).
So, who'd have thought that I'd have fun spending 4 days (25 hours) discussing...
The Commutative, Associative and Distributive Properties
Order of Operations (PEMDAS)
Decimal Points and Percentages
The way we teach math nowadays is a far cry from the "Yours is not to reason why, just invert and multiply" mentality of my childhood. It is unsurprising that I am lacking mathematical confidence after an education wherein traditional algorithms replaced an understanding of how numbers work.
I learned to "carry the one" but wasn't taught that the "one" was actually a "ten".
Today the traditional algorithms for addition, subtraction, multiplication and division are taught after the children have developed an understanding of our number system. In kindergarten we explore basic numbers and each successive grade builds on that understanding.
It's truly incredible to listen to children explain how they mentally solved a math problem by manipulating the numbers into "friendly" or "landmark" numbers and giving the parts meaning. For example (taken from the book pictured above), 38 + 25 could be solved as 30 + 20 = 50 then 8 + 5 = 13 then adding these two numbers together to get your answer 50 + 8 = 63. Or another child might try it this way, 38 + 2 = 40 then 40 + 20 = 60 so 60 + 3 = 63. There are so many possible ways to figure this out and the tradition algorithm is simply one of many.
Interestingly, once children develop number sense, the traditional way I learned of "borrowing" and "carrying" becomes the most confusing, complicated one of them all!
Kudos to our workshop leaders, Kerry and Christina, for making me as smart as fifth grader!
Check out the Common Core Alignment Guidance for Everyday Mathematics. Lessons in Everyday Math are color coded according to relevance to the Common Core.