Multi-Digit Addition Using A Number Line

This past week I introduced our students to the first of three strategies for adding multi-digit numbers, using the open number line.  For most parents, this strategy is new. When we were in school, we were taught the traditional algorithm (stack and add, carry the ten when needed). For several of us, this strategy worked...we could be consistently accurate using the algorithm. Unfortunately, many of our classmates were not so lucky and math started to not make sense to them. Our hope in teaching math now, is to introduce students to a few strategies and then allow the child to choose the strategy that works best for them...allowing them to experience success and understanding without frustration. 

Over the last two days I have watched several YouTube videos of teachers explaining the open number line method, in an attempt to find one that explains it the way I do. I was about to give up and accept the fact that I would have to make my own video and get my own YouTube account, when I took one last look and found this video! Thank goodness! 

Please watch the short video to hear the explanation of this strategy. You might recognize the steps as how you would mentally calculate a sum of two multi-digit numbers. 

* the only difference between how I teach it! is that my number line (the actual line) is invisible. I find that when the students draw the line things get messy. 

http://youtu.be/G9dHMtGAv5g

The benefits of this strategy are:

- students work at their level (some students will jump to "friendly" numbers, others will jump each ten or one separately)

- it builds on their understanding of place value (some students struggle to grasp the abstract concept of place value and they quickly become lost in the algorithm when they have to "carry a ten forward")

- it is great preparation for developing mental math strategies

All students brought math homework home this weekend (except for Connor, Avaya and Max). Please have them use this strategy to complete the questions. If you have any questions, please email me and I will do my best to call you back. 

****If your child forgot their homework at school (or if you want extra practice for them), grab a deck of cards. Remove the 10, J, Q and K. Have them deal out 2 two digit numbers for themselves and then add them up on a piece of paper using the number line strategy. Repeat this 10-20 times, depending on their accuracy. 

Happy Adding!