Why are people going on about memorizing doubles? Would you complain if they were memorizing the times tables? Well, what do you think the "2" times table is ... doubles! So, your 1/2nd grader is already memorizing the 2 times tables. Sheesh.

Anonymous wrote:

Anonymous wrote:
Who has change in their pocket anymore? My kids (not yet in second grade) don't know how to count change because they've never seen it. They can't tell a quarter from a penny.

That's not the only problem. They couldn't sum the prices either. Like 25c+50c+10c. They couldn't add.
I should have asked their teacher to come in and witness this. Maybe she would show them how to use doubles, 50+50-15 because that makes just as much sense.

This was a problem a few years ago when I was working with some teachers in a DCPS elementary school as a guest teacher. I asked them what they wanted me to address with their students, and they all wanted money sense. Not because they couldn't add or subtract double-digit numbers, but because they couldn't understand the real-life application: with credit and debit cards, few of them has ever seen their parents make change!

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:
And yes, the way it's solved actually is relevant. If the only thing you know about 7 + 8 is that the right answer is 15, then you haven't met the standards -- and what's more, your math understanding is less than it ought to be.

Oh, please, at 6 years old that's the only thing you should know.

Doubles is an irrelevant, hardly useful trick for addition and we should not be spending all this time on learning doubles. We should be spending this time on learning how to add and subtract double digit numbers. Then maybe kids will be able to count the change in their pocket in the second grade.

I'm beginning to think that this is what the school's math curriculum is - a set of tricks with lack of solid foundation.

Who has change in their pocket anymore? My kids (not yet in second grade) don't know how to count change because they've never seen it. They can't tell a quarter from a penny.

We are in MCPS. Some of their math work from school has been counting coins - 1st and 2nd grade. I suggest you practice at home if your school is not teaching your kids how to count coins. Yes, coins are still used, and your kids should know at least the denominations. Also helps teach fractions.

The Singapore math, US edition, home instructors guide, also has a schedule for where kids should be with math automaticity. There is definitely a point at which they are expected to have doubled memorized.

Anonymous wrote:

That's what I said, additions using tens and ones. No, no memorization in SM. Please note that doubles require memorization.

So my point is the stronger math schools don't use these tricks and don't waste time on them. In DD's class it's THE MAIN thing they're focusing on. Instead of reinforcing make-ten strategy. The problems are written in a very confusing ways for kids. I myself have to read them 3 times before I understand what they expect. All it does is confuses my kid to no end and it's not because she has a reading and comprehension problem. She does not have comprehension problems outside CC textbook.

Of course there is memorization in Singapore Math, or at least there is certainly memorization in math in Singapore. Those kids aren't doing 7 + 3 + 5 every time they see 7 + 8.

Also, doubles are not a "trick" -- unless make-ten is also a trick? Both are strategies. You might not like the doubles strategy, but that doesn't mean it's useless or harmful. It's just another strategy.

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

That's not the way Singapore Math looks at it.

I've been following SM U.S. addition for 2 years now. And there are not doubles there. The only strategies they're teaching are counting on or addition using tens and ones.

That is incorrect. Singapore Math also uses a lot of the make-ten strategy. In any case, what Singapore Math does NOT do is simply expect students to memorize that 7 + 8 = 15 and that's that.

You're right that there is no explicit mention of doubles, but so what?

That's what I said, additions using tens and ones. No, no memorization in SM. Please note that doubles require memorization.

So my point is the stronger math schools don't use these tricks and don't waste time on them. In DD's class it's THE MAIN thing they're focusing on. Instead of reinforcing make-ten strategy. The problems are written in a very confusing ways for kids. I myself have to read them 3 times before I understand what they expect. All it does is confuses my kid to no end and it's not because she has a reading and comprehension problem. She does not have comprehension problems outside CC textbook.

As PP said, it's really just the textbooks that are confusing. And at the lower grades, CC and SM emphasize going slowly over concepts, repeating them, etc. Go slowly to go fast later.

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

That's not the way Singapore Math looks at it.

I've been following SM U.S. addition for 2 years now. And there are not doubles there. The only strategies they're teaching are counting on or addition using tens and ones.

That is incorrect. Singapore Math also uses a lot of the make-ten strategy. In any case, what Singapore Math does NOT do is simply expect students to memorize that 7 + 8 = 15 and that's that.

You're right that there is no explicit mention of doubles, but so what?

That's what I said, additions using tens and ones. No, no memorization in SM. Please note that doubles require memorization.

So my point is the stronger math schools don't use these tricks and don't waste time on them. In DD's class it's THE MAIN thing they're focusing on. Instead of reinforcing make-ten strategy. The problems are written in a very confusing ways for kids. I myself have to read them 3 times before I understand what they expect. All it does is confuses my kid to no end and it's not because she has a reading and comprehension problem. She does not have comprehension problems outside CC textbook.

Anonymous wrote:

Anonymous wrote:

That's not the way Singapore Math looks at it.

I've been following SM U.S. addition for 2 years now. And there are not doubles there. The only strategies they're teaching are counting on or addition using tens and ones.

That is incorrect. Singapore Math also uses a lot of the make-ten strategy. In any case, what Singapore Math does NOT do is simply expect students to memorize that 7 + 8 = 15 and that's that.

You're right that there is no explicit mention of doubles, but so what?

Anonymous wrote:
Who has change in their pocket anymore? My kids (not yet in second grade) don't know how to count change because they've never seen it. They can't tell a quarter from a penny.

That's not the only problem. They couldn't sum the prices either. Like 25c+50c+10c. They couldn't add.
I should have asked their teacher to come in and witness this. Maybe she would show them how to use doubles, 50+50-15 because that makes just as much sense.

Anonymous wrote:

Oh, please, at 6 years old that's the only thing you should know.

Doubles is an irrelevant, hardly useful trick for addition and we should not be spending all this time on learning doubles. We should be spending this time on learning how to add and subtract double digit numbers. Then maybe kids will be able to count the change in their pocket in the second grade.

I'm beginning to think that this is what the school's math curriculum is - a set of tricks with lack of solid foundation.

Like this, you mean?

CCSS.Math.Content.2.NBT.B.5
Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction.

CCSS.Math.Content.2.NBT.B.6
Add up to four two-digit numbers using strategies based on place value and properties of operations.

CCSS.Math.Content.2.NBT.B.7
Add and subtract within 1000, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method. Understand that in adding or subtracting three-digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds.

As it happens, the Common Core standards for counting money are also for second grade (though I do wonder how many second-graders have change in their pockets):

CCSS.Math.Content.2.MD.C.8
Solve word problems involving dollar bills, quarters, dimes, nickels, and pennies, using $ and ¢ symbols appropriately. Example: If you have 2 dimes and 3 pennies, how many cents do you have?

Anonymous wrote:

That's not the way Singapore Math looks at it.

I've been following SM U.S. addition for 2 years now. And there are not doubles there. The only strategies they're teaching are counting on or addition using tens and ones.

Anonymous wrote:

Anonymous wrote:
And yes, the way it's solved actually is relevant. If the only thing you know about 7 + 8 is that the right answer is 15, then you haven't met the standards -- and what's more, your math understanding is less than it ought to be.

Oh, please, at 6 years old that's the only thing you should know.

Doubles is an irrelevant, hardly useful trick for addition and we should not be spending all this time on learning doubles. We should be spending this time on learning how to add and subtract double digit numbers. Then maybe kids will be able to count the change in their pocket in the second grade.

I'm beginning to think that this is what the school's math curriculum is - a set of tricks with lack of solid foundation.

That's not the way Singapore Math looks at it.

Also, I wouldn't call understanding that 7 + 7 + 1 = 15 or 7 + 3 + 5 = 15 or 8 + 8 - 1 = 15 "tricks". I would call it number sense. But maybe we're just using different words for the same thing.

Anonymous wrote:

Anonymous wrote:
And yes, the way it's solved actually is relevant. If the only thing you know about 7 + 8 is that the right answer is 15, then you haven't met the standards -- and what's more, your math understanding is less than it ought to be.

Oh, please, at 6 years old that's the only thing you should know.

Doubles is an irrelevant, hardly useful trick for addition and we should not be spending all this time on learning doubles. We should be spending this time on learning how to add and subtract double digit numbers. Then maybe kids will be able to count the change in their pocket in the second grade.

I'm beginning to think that this is what the school's math curriculum is - a set of tricks with lack of solid foundation.

Who has change in their pocket anymore? My kids (not yet in second grade) don't know how to count change because they've never seen it. They can't tell a quarter from a penny.

Anonymous wrote:
And yes, the way it's solved actually is relevant. If the only thing you know about 7 + 8 is that the right answer is 15, then you haven't met the standards -- and what's more, your math understanding is less than it ought to be.

Oh, please, at 6 years old that's the only thing you should know.

Doubles is an irrelevant, hardly useful trick for addition and we should not be spending all this time on learning doubles. We should be spending this time on learning how to add and subtract double digit numbers. Then maybe kids will be able to count the change in their pocket in the second grade.

I'm beginning to think that this is what the school's math curriculum is - a set of tricks with lack of solid foundation.

Anonymous wrote:

Anonymous wrote: That might seem like a small semantic argument, but it gets a lot of people confused about the issue.

It wouldn't be so if the textbooks didn't say "CC worksheet" on every page.

Also, the tests are exactly the same as textbooks. It's not the right answer that gets graded, but the way it's solved.

They don't ask DD to calculate 7+8, they ask her to do it their way as the only right way. If she doesn't use doubles and calculates it by making tens and ones, it's a wrong answer.

My DC meets the CC standards having been taught by SM curriculum.

They could say "Written on the moon by Copernicus" on every page. That wouldn't make it true.

And yes, the way it's solved actually is relevant. If the only thing you know about 7 + 8 is that the right answer is 15, then you haven't met the standards -- and what's more, your math understanding is less than it ought to be.