# Common Core Math

**URL:** <https://boards.straightdope.com/t/common-core-math/821118>\
**Category:** The BBQ Pit\
**Created:** [September 10, 2018, 7:27pm UTC](https://boards.straightdope.com/t/common-core-math/821118 "2018-09-10T19:27:12Z")\
**Posts on this page:** 20\
**Page:** 3

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**Author:** ![Apollyon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/apollyon/32/4238_2.png) [@Apollyon](https://boards.straightdope.com/u/Apollyon)\
**Post date:** [September 10, 2018, 9:02pm UTC](https://boards.straightdope.com/t/common-core-math/821118/41 "2018-09-10T21:02:29Z")

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> [@andros](#):
>
> But having seven three dollar bills is obviously not the same as having three seven dollar bills, even when your total is 21 dollars.

I dunno, in both cases you have $21 of rather poorly thought out counterfeit currency. 😃

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**Author:** ![Buck\_Godot](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/buck_godot/32/6573_2.png) [@Buck\_Godot](https://boards.straightdope.com/u/Buck_Godot)\
**Post date:** [September 10, 2018, 9:04pm UTC](https://boards.straightdope.com/t/common-core-math/821118/42 "2018-09-10T21:04:06Z")

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What is missing for those parents who complain about these sorts of problems is that none of them actually attended the lesson where these concepts and methods were taught.

This problem wasn’t just spring out of the blue on their precious little angel, from a vengeful teacher who takes pleasure marking papers wrong. It was done at the end of a hour long lesson describing the method they want to kids to use on that worksheet along with a whole host of examples. Today we will learn that 3 times 7 means the addition of 7 threes in a row. Next week we might point out that this is the same as 3 sevens in a row, but that is not what we are learning today. Today we are working on this particular understanding of what multiplication means.

If they just wanted to know the answer the kids could google it on their cell phones.

Now I can understand if your sweet little nugget of blessedness spent the whole lesson watching Jim in the next chair over to play with his booger, and then came home to ask you to do their homework you might not guess the lesson plan correctly and feel the wrath of a thousand suns that the teacher had the temerity to mark it wrong. But for the purpose of that lesson, it was indeed wrong, and your adorable dumpling of innocence needs to spend less time looking a boogers and more time paying attention in class.

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**Author:** ![Buck\_Godot](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/buck_godot/32/6573_2.png) [@Buck\_Godot](https://boards.straightdope.com/u/Buck_Godot)\
**Post date:** [September 10, 2018, 9:12pm UTC](https://boards.straightdope.com/t/common-core-math/821118/43 "2018-09-10T21:12:18Z")

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It also might be easier to see it from the point of view of higher mathematics. If I was teaching factoring polynomials, I might ask

Solve X^2 - X -12 = 0 for X. The correct was would be to factor it into (X-4)(X+3) = 0 so that X = 4 or -3

If the student solved this using the quadratic formula, I would mark it wrong because he didn’t demonstrate an understanding of factoring polynomials.

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**Author:** ![Johnny\_Bravo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_bravo/32/493_2.png) [@Johnny\_Bravo](https://boards.straightdope.com/u/Johnny_Bravo)\
**Post date:** [September 10, 2018, 9:20pm UTC](https://boards.straightdope.com/t/common-core-math/821118/44 "2018-09-10T21:20:27Z")

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> [@Buck\_Godot](#):
>
> If the student solved this using the quadratic formula, I would mark it wrong because he didn’t demonstrate an understanding of factoring polynomials.

Right. Education isn’t always about getting the “right” answer - it’s about learning specific processes or skills.

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**Author:** ![Damuri\_Ajashi](https://avatars.discourse-cdn.com/v4/letter/d/898d66/32.png) [@Damuri\_Ajashi](https://boards.straightdope.com/u/Damuri_Ajashi)\
**Post date:** [September 10, 2018, 9:33pm UTC](https://boards.straightdope.com/t/common-core-math/821118/45 "2018-09-10T21:33:34Z")

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> [@Ravenman](#):
>
> I’ve watched a few YouTube videos on how math is being taught these days. Though I had no freaking clue what all the squiggles and dots meant when they were just put in front of me, after some explanation I think it’s pretty clear that these are novel ways to explain math in ways I rather wish I had some exposure to when I was in school.
> 
> The comparison to martial arts is apt. Martial arts is not simply about repetition and rote memorization of various techniques. If you want to execute some kind of takedown, it’s reasonable to expect a decent student to show not only that they can execute the technique if the attacker starts in ready position; steps forward with a single punch; and basically pauses until the defender can execute the technique they have memorized. They should understand both how to adapt the technique to unplanned situations, and grok why the technique works to begin with.
> 
> Learning how imbalances among several axes on someone’s body will make them fall down – that is, the basic principle of a takedown – adds context to the action and allows a person to tinker with their technique and experiment with the principles in order to become better.
> 
> So, in the same manner – teaching kids some of the principles behind math in order for them to know how to solve the problem in various ways seems like a good idea; demanding that the multiplication tables AND NOTHING ELSE DAMMIT be pounded into their head seems like a poor idea.

Who is demanding the memorization of multiplication tables and NOTHING ELSE DAMMIT be pounded into their heads?

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**Author:** ![Damuri\_Ajashi](https://avatars.discourse-cdn.com/v4/letter/d/898d66/32.png) [@Damuri\_Ajashi](https://boards.straightdope.com/u/Damuri_Ajashi)\
**Post date:** [September 10, 2018, 9:35pm UTC](https://boards.straightdope.com/t/common-core-math/821118/46 "2018-09-10T21:35:05Z")

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> [@Strassia](#):
>
> If you are working in pure math sure. In the real world sometimes it matters. Take eggs.
> 
> Eggs come in cartons of 12. If you are just counting cartons and figuring out how many eggs you have then you can do X_12 or 12_X and get the right answer. But if have a more complex question it matters if they understand how the concept is being applied.
> 
> Common core shifts some of the emphasis from memorizing math facts (they are still taught, just not as emphasized) to math sense. Understanding how numbers work and why. There are a lot of math algorithms that are either no longer taught or emphasized. My algebra teacher showed us the algorithm for finding square roots once, just so we could see it. I have never used or or seen it since. Is that problem?
> 
> My 6th grade just brought home a worksheet on factoring. When I did it, I would have had to shown how I divided each large number by the possible factors to determine if there was a remainder. His wanted him to explain how he eliminated each one: Didn’t end in 0 or 5, added digits and weren’t divisible by 3, etc. Those were “tricks” I learned in SAT prep. He even had ones that I never saw before. His way was much faster and, if done properly, will give him a better basis for understanding how bases work later on.

If this is an improvement then why in the world is our relative math proficiency dropping relative to countries that are teaching math the “old” way.

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**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\
**Post date:** [September 10, 2018, 9:41pm UTC](https://boards.straightdope.com/t/common-core-math/821118/47 "2018-09-10T21:41:29Z")

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This is “the old way”.

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**Author:** ![Measure\_for\_Measure](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/measure_for_measure/32/557_2.png) [@Measure\_for\_Measure](https://boards.straightdope.com/u/Measure_for_Measure)\
**Post date:** [September 10, 2018, 9:44pm UTC](https://boards.straightdope.com/t/common-core-math/821118/48 "2018-09-10T21:44:18Z")

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As of 2012, math scores in the 9 year old set were growing by leaps and bounds. So I’m dubious about the evils of common core.

The problem is that the gains dissipate in high school. [The Kids Are All Right – Mother Jones](https://www.motherjones.com/politics/2012/08/kids-school-test-scores-charts-kevin-drum/)  
Ok, but how are we doing internationally?  
[INDENT] In 8th grade math, American students ranked ninth out of the 56 educational systems that participated in the testing, behind five Asian countries and three others. Average scores are up 17 points since 1995. [/INDENT] [How Do American Kids Stack Up on Math, Science, and Reading? – Mother Jones](https://www.motherjones.com/kevin-drum/2012/12/how-do-american-kids-stack-math-science-and-reading/)

The OP calls that outrage? **This** is outrage, courtesy of an American Spectator piece of spam that I once subscribed to for my amusement: **According to Common Core, soft-core porn is preferable to Jane Austen**. _That’s_ outrageous if true, and is swallowed whole by gullible morons. Google it: that proves it! BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD.

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<div class="post-metadata">

**Author:** ![Damuri\_Ajashi](https://avatars.discourse-cdn.com/v4/letter/d/898d66/32.png) [@Damuri\_Ajashi](https://boards.straightdope.com/u/Damuri_Ajashi)\
**Post date:** [September 10, 2018, 9:46pm UTC](https://boards.straightdope.com/t/common-core-math/821118/49 "2018-09-10T21:46:35Z")

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> [@Buck\_Godot](#):
>
> What is missing for those parents who complain about these sorts of problems is that none of them actually attended the lesson where these concepts and methods were taught.
> 
> This problem wasn’t just spring out of the blue on their precious little angel, from a vengeful teacher who takes pleasure marking papers wrong. It was done at the end of a hour long lesson describing the method they want to kids to use on that worksheet along with a whole host of examples. Today we will learn that 3 times 7 means the addition of 7 threes in a row. Next week we might point out that this is the same as 3 sevens in a row, but that is not what we are learning today. Today we are working on this particular understanding of what multiplication means.
> 
> If they just wanted to know the answer the kids could google it on their cell phones.
> 
> Now I can understand if your sweet little nugget of blessedness spent the whole lesson watching Jim in the next chair over to play with his booger, and then came home to ask you to do their homework you might not guess the lesson plan correctly and feel the wrath of a thousand suns that the teacher had the temerity to mark it wrong. But for the purpose of that lesson, it was indeed wrong, and your adorable dumpling of innocence needs to spend less time looking a boogers and more time paying attention in class.

Do you have kids? If doubt anyone would fuck you other than yourself but if you did somehow manages to impregnate someone else without that person immediately swallowing a tub of Plan B and getting their uterus removed, they probably gave birth to really dumb kids that NEED common core to understand simple math. We are dumbing down America in an effort to avoid reinforcing your kids well deserved feelings of inadequacy. If you think Trump is bad, your kid is probably going to be one of the dumb fucks that vote for someone even worse than Trump in order to “fix” social security and Medicare.

TLDR: Why the fuck are you insulting my kid in a discussion of common core you fucking waste of sperm?

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<div class="post-metadata">

**Author:** ![Damuri\_Ajashi](https://avatars.discourse-cdn.com/v4/letter/d/898d66/32.png) [@Damuri\_Ajashi](https://boards.straightdope.com/u/Damuri_Ajashi)\
**Post date:** [September 10, 2018, 9:50pm UTC](https://boards.straightdope.com/t/common-core-math/821118/50 "2018-09-10T21:50:46Z")

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> [@Measure\_for\_Measure](#):
>
> As of 2012, math scores in the 9 year old set were growing by leaps and bounds. So I’m dubious about the evils of common core.
> 
> The problem is that the gains dissipate in high school. [The Kids Are All Right – Mother Jones](https://www.motherjones.com/politics/2012/08/kids-school-test-scores-charts-kevin-drum/)  
> Ok, but how are we doing internationally?  
> [INDENT] In 8th grade math, American students ranked ninth out of the 56 educational systems that participated in the testing, behind five Asian countries and three others. Average scores are up 17 points since 1995. [/INDENT] [How Do American Kids Stack Up on Math, Science, and Reading? – Mother Jones](https://www.motherjones.com/kevin-drum/2012/12/how-do-american-kids-stack-math-science-and-reading/)
> 
> The OP calls that outrage? **This** is outrage, courtesy of an American Spectator piece of spam that I once subscribed to for my amusement: **According to Common Core, soft-core porn is preferable to Jane Austen**. _That’s_ outrageous if true, and is swallowed whole by gullible morons. Google it: that proves it! BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD.

> **[U.S. students’ academic achievement still lags that of their peers in many...](https://www.pewresearch.org/short-reads/2017/02/15/u-s-students-internationally-math-science/)**
>
> U.S. students continue to rank near the middle, and behind many other advanced industrial nations, in international math, science and reading assessments.

It was never great but it used to be better. So tell me again how great common core math is. I don’t really notice a difference in common core reading except they seem to be teaching more critical reading skill earlier. its not that hard to fuck that up I suppose.

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<div class="post-metadata">

**Author:** ![Measure\_for\_Measure](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/measure_for_measure/32/557_2.png) [@Measure\_for\_Measure](https://boards.straightdope.com/u/Measure_for_Measure)\
**Post date:** [September 10, 2018, 10:11pm UTC](https://boards.straightdope.com/t/common-core-math/821118/51 "2018-09-10T22:11:56Z")

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> [@Damuri\_Ajashi](#):
>
> [U.S. academic achievement lags that of many other countries | Pew Research Center](http://www.pewresearch.org/fact-tank/2017/02/15/u-s-students-internationally-math-science/)
> 
> It was never great but it used to be better. So tell me again how great common core math is. I don’t really notice a difference in common core reading except they seem to be teaching more critical reading skill earlier. its not that hard to fuck that up I suppose.

From the link, “After years of growth, math proficiency of US students dips”. The 8th grader chart shows steady improvement from 1990 to 2013. Then there’s a dip in 2015. Ditto for 4th graders.

One blip isn’t a trend. Your characterization is inaccurate.

BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD.

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<div class="post-metadata">

**Author:** ![Damuri\_Ajashi](https://avatars.discourse-cdn.com/v4/letter/d/898d66/32.png) [@Damuri\_Ajashi](https://boards.straightdope.com/u/Damuri_Ajashi)\
**Post date:** [September 10, 2018, 10:28pm UTC](https://boards.straightdope.com/t/common-core-math/821118/52 "2018-09-10T22:28:56Z")

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> [@Measure\_for\_Measure](#):
>
> From the link, “After years of growth, math proficiency of US students dips”. The 8th grader chart shows steady improvement from 1990 to 2013. Then there’s a dip in 2015. Ditto for 4th graders.
> 
> One blip isn’t a trend. Your characterization is inaccurate.
> 
> BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD. BUY GOLD.

What is with the buy gold spam?

And I did a word search for “after years of growth” on my link or your Mother Jones link and I cannot find it. Perhaps you are thinking of a different link?

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**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\
**Post date:** [September 10, 2018, 10:30pm UTC](https://boards.straightdope.com/t/common-core-math/821118/53 "2018-09-10T22:30:12Z")

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> [@SingleMalt](#):
>
> Keep in mind that this is an approach used when first learning multiplication. For those newly exposed to the concept of multiplication, the associative, commutative, and distributive properties of multiplication are a foreign concept.
> 
> It is perfectly natural, then, to present the expression “3 x 7” as “three groups of seven” and “7 x 3” as “seven groups of three”. Remember, these kids don’t know that multiplication commutates, so they don’t intuitively know that “3 x 7” is equivalent to saying “7 x 3”. This concept is yet to come.
> 
> “Seven groups of three” and “three groups of seven” may have the same total, but they are not the same.

> [@Johnny\_Bravo](#):
>
> Right. Education isn’t always about getting the “right” answer - it’s about learning specific processes or skills.

But commutativity is not a difficult concept, and a kid may well have grasped it before it has been explicitly taught, especially if rectangles of dots are being used - by noticing that three rows of seven makes the exact same shape as seven rows of three. If you’ve noticed this, it’s sensible to exploit the fact that adding fewer large numbers is easier than adding more small numbers.

Surely nobody should ever be marked wrong for using a _valid_ method solely because it’s more advanced, unless showing working using a specific method was explicitly required for the exercise (as in the quadratic factoring example).

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**Author:** ![Measure\_for\_Measure](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/measure_for_measure/32/557_2.png) [@Measure\_for\_Measure](https://boards.straightdope.com/u/Measure_for_Measure)\
**Post date:** [September 10, 2018, 10:33pm UTC](https://boards.straightdope.com/t/common-core-math/821118/54 "2018-09-10T22:33:56Z")

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> [@Damuri\_Ajashi](#):
>
> And I did a word search for “after years of growth” on my link or your Mother Jones link and I cannot find it. Perhaps you are thinking of a different link?

It’s in the image. 2nd chart.

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**Author:** ![Ravenman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ravenman/32/2929_2.png) [@Ravenman](https://boards.straightdope.com/u/Ravenman)\
**Post date:** [September 10, 2018, 10:36pm UTC](https://boards.straightdope.com/t/common-core-math/821118/55 "2018-09-10T22:36:59Z")

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> [@Damuri\_Ajashi](#):
>
> Who is demanding the memorization of multiplication tables and NOTHING ELSE DAMMIT be pounded into their heads?

You’re the one proclaiming that Amurka is goin’ down the tubes because of New Math.

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**Author:** ![Left\_Hand\_of\_Dorkness](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/left_hand_of_dorkness/32/7156_2.png) [@Left\_Hand\_of\_Dorkness](https://boards.straightdope.com/u/Left_Hand_of_Dorkness)\
**Post date:** [September 10, 2018, 11:01pm UTC](https://boards.straightdope.com/t/common-core-math/821118/56 "2018-09-10T23:01:43Z")

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> [@Damuri\_Ajashi](#):
>
> This has probably been covered already but…
> 
> WTF is this bullshit!!!
> 
> It seems like math for people who can’t grokk math.
> 
> Can’t they just put all the slower kids in a different class and teach them common core?
> 
> Question: 7\*3
> 
> 7+7+7=21 WRONG
> 
> 3+3+3+3+3+3+3=21 RIGHT

People who rant about things they haven’t educated themselves about first are stupid.

Common Core standards (and literally all Common Core is is the standards, it’s not the implementation, that’s as different as Leviticus is from the Methodist Church) are fine with the commutative property.

Last year, a couple of my friends had a daughter in third grade, and something similar happened. She came home with a worksheet where she’d solved the problem “5 x 4” by writing “5 + 5 + 5 + 5 = 20”, and it was marked wrong. My friend posted it on Facebook and asked if any of his elementary teacher buddies could explain the thinking.

I could. I recognized that worksheet from the curriculum my district mandates. So I went to the teacher manual for that unit and took a photo of the teacher note that emphasized the commutative property and told teachers straight-out to allow students to solve problems using it (unfortunately, the teacher note had a critical typo in it that made it hard to understand–I hate Pearson, but that’s another matter).

He showed it to the teacher. She wouldn’t budge. He showed it to the principal. She wouldn’t budge. Finally he went to the district math coach and organized a conference between the principal, the teacher, and the math coach, and achieved victory–but got scolded by the principal for posting about the matter on Facebook (she’d Facebook stalked him and learned about it).

My friend never pulled out the big guns: he never explained that he and his wife both have their masters degrees in mathematics and teach math at the high school and college level respectively.

* * *

You’re saying, basically, that some teachers are teaching math poorly. (You were apparently taught poorly, given your statistical innumeracy above–but I’m not sure your teachers were at fault). Guess what?

If you pay teachers significantly below the going wages for college graduates, and far below the wages for college graduates with a strong math background, you’re gonna end up with a significant number of elementary school teachers who are uncomfortable with thinking mathematically and who will treat the textbook as a poorly-understood series of incantations, instead of as a fascinating set of logical puzzles to solve.

Stop shitting on common core math, and start shitting on legislatures that insist on keeping education wages low enough to drive off lots of qualified teachers.

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<div class="post-metadata">

**Author:** ![glowacks](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/glowacks/32/5548_2.png) [@glowacks](https://boards.straightdope.com/u/glowacks)\
**Post date:** [September 10, 2018, 11:35pm UTC](https://boards.straightdope.com/t/common-core-math/821118/57 "2018-09-10T23:35:26Z")

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> [@Riemann](#):
>
> Surely nobody should ever be marked wrong for using a _valid_ method solely because it’s more advanced, unless showing working using a specific method was explicitly required for the exercise (as in the quadratic factoring example).

I was marked wrong in grad school for using a concept in a problem that we would learn the next week. In computational number theory problems. The teacher wanted us to use the hard way to appreciate the easy way. I had already learned so much of the course previously that I didn’t bother paying attention to what had been gone over in class. It’s the same sort of thing as teachers marking 3rd graders wrong for not following the method that was just taught. It’s ingrained that students must learn every single lesson and show that they understand that particular lesson, even if they have no reason to understand it in the long run because they already understand much more advanced concepts.

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<div class="post-metadata">

**Author:** ![Buck\_Godot](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/buck_godot/32/6573_2.png) [@Buck\_Godot](https://boards.straightdope.com/u/Buck_Godot)\
**Post date:** [September 11, 2018, 12:09am UTC](https://boards.straightdope.com/t/common-core-math/821118/58 "2018-09-11T00:09:10Z")

</div>

> [@Damuri\_Ajashi](#):
>
> Do you have kids? If doubt anyone would fuck you other than yourself but if you did somehow manages to impregnate someone else without that person immediately swallowing a tub of Plan B and getting their uterus removed, they probably gave birth to really dumb kids that NEED common core to understand simple math. We are dumbing down America in an effort to avoid reinforcing your kids well deserved feelings of inadequacy. If you think Trump is bad, your kid is probably going to be one of the dumb fucks that vote for someone even worse than Trump in order to “fix” social security and Medicare.
> 
> TLDR: Why the fuck are you insulting my kid in a discussion of common core you fucking waste of sperm?

Sorry, for some reason I was feeling an a Pitting mood and let loose.

It wasn’t really meant so much as an attack on your kid, (at that age what kid wouldn’t be more fascinated with boogers than a boring math lecture), as an attack on the attitude that if a student didn’t learn that material and didn’t follow the directions in class that it must be the teacher or the Liberal establishments fault all without even contacting the teacher to figure out what the purpose of the lesson was.

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<div class="post-metadata">

**Author:** ![Left\_Hand\_of\_Dorkness](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/left_hand_of_dorkness/32/7156_2.png) [@Left\_Hand\_of\_Dorkness](https://boards.straightdope.com/u/Left_Hand_of_Dorkness)\
**Post date:** [September 11, 2018, 12:11am UTC](https://boards.straightdope.com/t/common-core-math/821118/59 "2018-09-11T00:11:11Z")

</div>

> [@glowacks](#):
>
> It’s the same sort of thing as teachers marking 3rd graders wrong for not following the method that was just taught. It’s ingrained that students must learn every single lesson and show that they understand that particular lesson, even if they have no reason to understand it in the long run because they already understand much more advanced concepts.

I teach my kids–and, at conferences, my kids’ parents–my three rules of evaluating a method for solving a math problem:

1. You get the right answer.
2. You understand why it works.
3. It doesn’t take you too long.

They’re all important, generally in that order. In the adult world, #2 doesn’t matter as much, but that’s because #1 is so much more important. For kids wrapping their heads around the world of numbers, though, #2 is real important.

I tell them that like 90% of the time I’m cool with whatever method they choose to solve problems, as long as it meets all 3 requirements. But I also tell them that RARELY, I’ll teach a specific new technique, and I’ll ask them to practice that technique so they can understand what’s good about it and decide whether it’s a good one for them. More tools in their mental toolbelt is better.

Long way of saying, I might ask them, for a day or two, to interpret a problem like “7 x 3” as “Seven groups of three,” or “Three, added together seven times.” If I did, I’d make it super-clear to them that this was a formality, that it was a way to help them translate real-world problems into mathematical symbols, and that apart from this lesson or two they could solve it any old way that met the three rules.

I would never, never, NEVER give them a worksheet that required a particular method without having explicit directions that explained that method.

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<div class="post-metadata">

**Author:** ![Damuri\_Ajashi](https://avatars.discourse-cdn.com/v4/letter/d/898d66/32.png) [@Damuri\_Ajashi](https://boards.straightdope.com/u/Damuri_Ajashi)\
**Post date:** [September 11, 2018, 12:58am UTC](https://boards.straightdope.com/t/common-core-math/821118/60 "2018-09-11T00:58:36Z")

</div>

> [@Ravenman](#):
>
> You’re the one proclaiming that Amurka is goin’ down the tubes because of New Math.

Really? So where do I say that the old math is memorizing the multiplication table and NOTHING ELSE?

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