I’m pretty stoked for a new blog hope idea that has been created by a pretty awesome group of mathematics educators (thanks Brandi from The Researched Based Classroom for organizing!. The plan is to bring you multiple perspectives on a joint topic every couple of months. This month there are 15 of us teaming up to bring you our thoughts on place value. Make sure to ‘hop’ through all 15 posts to pick up some ideas about how you can use place value in your classroom! You may even find a freebie, or product along the way that will help out as well. Many perspectives and grade levels are covered. I do hope you will enjoy our new endeavor!
This past week I attended a state level mathematics supervision meeting and had the pleasure of hearing Dr. Sherry Parrish speak. Dr. Parrish, or Sherry as she told me to call her (say what?!) is the author of the book Number Talks
Now, I’m not expecting you to look at the entire video right now (though, if you have the time it is ABSOLUTELY worth watching in entirety), I would, however like you to watch the first 8 minutes, paying close attention around from about 3:30 to around 7:00.
Did you hear what the student’s responded to Sherry? Okay… so there’s an issue! The kids know the algorithm, they know how to get the “right answer” but they clearly have no conception of what their numbers mean. They have not made the connection between place value and their algorithms.
So, what can we as teachers students see the place value connections?
Personally, I think we teach alternate algorithms FIRST and then we start helping the students make the connections to the ‘more efficient’ traditional algorithm. Let’s look at a example traditional problems and then look at some alternatives:
Pro : Efficient
Con: What does that little 2 stand for? Why do we shift the second line or add a zero? Is it 5×2 or is it 5×20. Little to no connection to what is happening.
Pro: Easy for students who aren’t great at multiplying. Organizes information easily
Con: If taught rotely and procedurally, makes as little connection to place value as the traditional method. Students needs to see the connection between the diagonals and place value.
Pro: Easy to set up, helps students with decomposition, instant link to place value, direct connection to multiplying polynomials using manipulatives in higher grades, helps students “see” why the traditional works when placed side-by-side, helps with mental math
Pro: helps students with decomposition, direct link to place value, helps students “see” why the traditional works when placed side-by-side, instant link to place value, helps with mental math
Con: can be cumbersome with 2,3,4 digit multiplication.
Donna from Math Coach’s Corner has a great blog post on using partial and area methods that you should also check out!
Okay, so you’ve seen some alternatives now. I don’t think that any of them is necessarily better than the other, but I DO think, that using the three alternatives FIRST is a great idea. Get the students to have a conceptual idea of the place value. Have them work fluently between the methods. Then, once they have a grasp of what is going on, see how they do with the traditional method. And, if a student prefers an alternate method… that’s okay!
Have you used alternate methods in your classroom? What are your thoughts? How can you help parents transition to one of these methods? I’d love to hear your thoughts!
Leave me a message letting me know your opinion and then head on over to Mr. Elementary Math by clicking on his icon to see what he has to say about place value