- Get link
- Other Apps
There is a Common Core "example" that is going around the internet right now that "shows" how the Common Core is going to DOOM (doom, doom) our kids for, like, ever! The example at Friendly Atheist (which is a bad example) looks like this:
Mehta's breakdown of why the "new" way actually makes more sense than the "old fashion" way is excellent even though we all look at the first example and know how to do it. Can you explain why it works? Easily? What if you had to "borrow" in the problem could you explain it then?
Full disclosure, I subtract this way and I can explain why it works and I think that many of the teachers I work with could explain why it works (even if they don't teach math). However, is this how you think of subtracting in your head? How do you think about math when you aren't doing math? When you tip 20%? When you measure and something needs to be 1 and 13/16th inchs shorter?
The point of the Common Core is in part to help build mathematical concepts based on how we already think about math. Algorithms are important, but why things work is even more important and how to do mental math is more important than the algorithm. I mean we do have calculators. How many of you make your kids write a paper and force them to turn off the red squiggly line? Thought so.
So mental math. How do we solve 234-147 mentally. First, you should estimate. 230-150 is 80. Is that close enough for what you're doing? No. Ok. Try this.147 is 3 away from 150, which is 50 away from 200, which is 34 away from 234: 3+50+34 is 87. Done! It's close to our estimate so we can be confident in our work.
For those of you that always complain about how cashiers can't give back proper change, this is the method that people are taught to give back change. Count up from what is owed to what is tendered. The Common Core is advocating for this "out of the classroom" number sense because math isn't just done in the classroom. Once students have a sense of numbers we can progress to traditional algorithms because now students understand why the methods work.
Teachers need training and support as we continue to reform how we teach.
Arthur Benjamin is an advocate for better mental math (and improving math education in general) and takes his show on the road. He ends this video by squaring a 5-digit number in his head. When I show this video to my students, regardless of the ability of the class, they always ask "How does he do that?" As a teacher, I know to show this video right before the Difference of Squares part of polynomial work because then they can see how and why what he does works (on a smaller scale, of course).
Think about how you do math every day and ask if the algorithms that we teach still make sense. I'm not saying abandon all the algorithms, but we need to allow different ways of thinking.
Mehta's breakdown of why the "new" way actually makes more sense than the "old fashion" way is excellent even though we all look at the first example and know how to do it. Can you explain why it works? Easily? What if you had to "borrow" in the problem could you explain it then?
Full disclosure, I subtract this way and I can explain why it works and I think that many of the teachers I work with could explain why it works (even if they don't teach math). However, is this how you think of subtracting in your head? How do you think about math when you aren't doing math? When you tip 20%? When you measure and something needs to be 1 and 13/16th inchs shorter?
The point of the Common Core is in part to help build mathematical concepts based on how we already think about math. Algorithms are important, but why things work is even more important and how to do mental math is more important than the algorithm. I mean we do have calculators. How many of you make your kids write a paper and force them to turn off the red squiggly line? Thought so.
So mental math. How do we solve 234-147 mentally. First, you should estimate. 230-150 is 80. Is that close enough for what you're doing? No. Ok. Try this.147 is 3 away from 150, which is 50 away from 200, which is 34 away from 234: 3+50+34 is 87. Done! It's close to our estimate so we can be confident in our work.
For those of you that always complain about how cashiers can't give back proper change, this is the method that people are taught to give back change. Count up from what is owed to what is tendered. The Common Core is advocating for this "out of the classroom" number sense because math isn't just done in the classroom. Once students have a sense of numbers we can progress to traditional algorithms because now students understand why the methods work.
Teachers need training and support as we continue to reform how we teach.
Arthur Benjamin is an advocate for better mental math (and improving math education in general) and takes his show on the road. He ends this video by squaring a 5-digit number in his head. When I show this video to my students, regardless of the ability of the class, they always ask "How does he do that?" As a teacher, I know to show this video right before the Difference of Squares part of polynomial work because then they can see how and why what he does works (on a smaller scale, of course).
Think about how you do math every day and ask if the algorithms that we teach still make sense. I'm not saying abandon all the algorithms, but we need to allow different ways of thinking.
Comments
Post a Comment