Thursday, 9 June 2016

Exploring Addition and Subtraction

We have intentionally set up our classroom to allow our learners the opportunity to explore and create with a variety of open-ended materials. The materials we choose allow learners to share their thinking at the level they are at. We can then come alongside them and push their thinking further. As we push out learners to think deeper, I am continually amazed at what they are capable of.

Practicing writing numbers, using a book to help. "Ms. Tompkins, the book is kind of like a teacher!"

We set out a simple provocation to encourage the exploration of adding and subtracting.




Our learners were excited about sharing their learning using these manipulatives.



Using a rekenrek to subtract.



A few of our learners were very eager to add double digit numbers, but quickly became overwhelmed by the number of counters they had to count. We wondered if there was a better way...


We then introduced the concept of grouping the cubes into tens and having groups of ten and then ones left over.  They began to create numbers (see above). They quickly took this new learning to help them add numbers together. We worked through a few examples together, both with and without regrouping. They picked it up so quickly! Now every time we turn around they are adding bigger and bigger numbers!


We have been challenging them to record their thinking so they can share their learning with the other mathematicians in the class.


Sharing his strategy with the class during out math meeting.


"I wonder how many cubes are in the basket?" A.R. and D.A. worked together to count the 353 cubes in our class! 

Not only are they working on adding through addition sentences, but many of our mathematicians are creating growing patterns.  I challenged I.L. to create a growing pattern by 2. We went through the first two numbers of the pattern and then she worked at continuing the pattern. I came back and saw 2, 4, 8. Thinking to myself, "Oh no, she skipped the number 6". I am so thankful I didn't say this out loud and instead asked, "what would come next?" She thought for a while and said "16!" She had been creating a doubling pattern! 


She wanted to know what would come next, but she ran out of materials in the sand table. A.A. said he would teach her his strategy to add 64 + 64. The two of them worked together and determined it was 128. 


Watch A.A describe his work:




Here is a growing and shrinking pattern. "You put one more every time!"
Never underestimate children. They truly are "splendid little mathematicians"!


**A few of our favourite adding songs:




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