This past Friday was my second day at the OCTM annual math conference and I chose to spend more time with the ladies from the Developmental Math Group. The focus for their session this time was place value. If you are teaching kindergarten and if you have switched to the Common Core then you know place value is something new in kindergarten for numbers through 20. Not only did they discuss place value but they shared nuggets of math goodness.
-acting out the math helps students see the process.
-asking the question, what do you know is crucial
-start with understanding
-symbols are abstract
-talking is powerful for students
-kids will listen to kids
-Kindergarten is good at showing, expressing is hard
-by modeling everyday situations math is put into context
Here are some highlights about place value relevant to our emerging mathematicians. Numbers have a place and a value. When kindergarten children come, they think of 23 as 23 ones not 2 tens and 3 ones. It's our job to move them to the base ten language system. Popsicle sticks bundled as tens are a great tool for working with place value in the beginning. The popsicle stick is the same shape and size. By using grouping types of all the same shape and size place and value become more concrete than if you were using different units. My new second favorite math word is unitizing - thinking of a numbers as a group. In kindergarten, we need to be thinking of place value as a group of ten ones and some more. They spent a great deal of time talking about the structure of the hundreds board and how important it is for the students to interact with the board to learn the structure. They also suggested it's easier for emerging mathematicians to work with a board 1-99 at first. They spent some time sharing great ideas for a place value mat and their own decimal mats they developed as visual models to increase understanding. If I taught older students they would be a must to have in my classroom. They shared a personal bug a boo - don't call place value blocks units, longs and flats. Here's their justification, "We don't develop meaningful mathematics if we don't use mathematical language." We ended our session with this quote that really brings home how important beginning mathematics is.
"A child who has number sense has common sense for mathematics."