## Wednesday, March 12, 2014

### Math Experimentation

I'm trying something new with my Friday estimation jar activity.  Typically we practice making reasonable estimations, group the candy by tens, count it, and eat it.  I'm attempting to integrate the open number line and just better number sense.  It's kind of an experiment.  Here's how it's going so far.

The person who brought the estimation jar filled with wrapped candy chooses three people to share their estimations which I write on the smartboard.  I draw an open number line and we put the estimations in order on the number line with proper spacing.  Then I draw another number line on the board and we start counting the candy.  When we get to ten, I talk about how I could make ten small hops or I could simply make one hop to ten. Every time we count another ten, I make another hop and so on until we've counted all the pieces.  Finally, we return to the three estimations from the beginning of the lesson, find where those numbers fit on our new number line, circle them, and see how close they were to the actual number.

Here are several examples.

I'm tweaking as I go, but I think I'm on to something that will help my mathematicians grasp the open number line better.  Eventually, I envision the kids doing this with me at their desks with their own number lines, following what Regie Routman says.  I do, we do, we do, we do, you do.

1. I don't think I do enough on the number line. Talk to me more about why this is so critical. I know you never do anything without believing in it and knowing exactly why. I am so interested. Do you have iPads? The app Motion Math: Zoom is all about number lines. My kids love it and learn so much.

1. Kimberley, great question. I'm sure some of my math coach friends could explain it better, but from what I'm hearing out in the math world, the open number line is one of the most efficient models for kids to use. It improves flexibility with numbers, number sense, mental math, etc. Here's a little something I found that might help. http://catalog.mathlearningcenter.org/files/media/rekenrek/numberline_overview.pdf
No, I don't have ipads yet. The app you mentioned sounds great!

2. Explore the work of John A. Van de Walle and Cathy Fosnot, both leading mathematicians for young children exploring number. An open number line is such a powerful tool as the students compose and decompose numbers. they look at 26 subtract 14 and can say "I will move back from 26 by 10 to make 16 and now move back another 4 to make 12...the answer to 26 subtract 14 is 12." They are demonstrating that they know that 14 is composed of one group of 10 and four units. They are demonstrating an understanding of how you use place value when you subtract, and the student who isn't ready for that step, is being exposed to other's thinking as they demonstrate their understanding. Maybe that lower student can demonstrate that to subtract 14, you could make backwards jumps of 2 - 7 times....and you can praise them and say "You just showed us a multiplication equation because 2 times 7 is 14...Aren't you clever!" I LOVE open number lines! The kids stop being afraid of math. They learn to play with numbers! They lose their fear of being wrong.
sherry-matheson.blogspot.com

1. I so agree Sherry. I've enjoyed Van de Walle and Fosnot too. It's been fun to see my kids explore number lines in the past few years. I feel like they're more prepared for second grade math.

3. Our students need a deeper level of number awareness too. I think building this knowledge at the base level is huge for students to be able to progress and really understand each step afterwards. Your students are ahead of the game because you are doing that!
Lori
Conversations in Literacy

1. Lori, it's pretty cool to see what they can do once they figure out how the number line works.