General Discussion

redgreenandblue

(2,128 posts)

229. Theoretical physicist here. I have my doubts that this is a good way to teach math.

Thu Oct 22, 2015, 08:46 AM

Oct 2015

I get that the task here was to correctly apply an algorithm. However, from a practical standpoint, I see no reason why learning this is a desirable goal. Part of math is figuring out the simplest way to solve a problem, not mindlessly applying some computational scheme. If commutativity allows the problem to be solved in less steps, then this is what should be done.

The only reason I can think of for demanding rigidity when applying an algorithm in the context of a pedagogical task, is when this algorithm is superior to the "shortcut" in a more general setting, or offers some new insight that the shortcut concealed. This doesn't seem to be the case here.

There is an interview with Richard Feynman, to which I currently don't have the link unfortunately, where he discusses exactly this issue. He basically argues that he was always good at math in school because he was able to solve the problem in a different way than what the recipe prescribed.

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Highlight:

Why Would a Math Teacher Punish a Child for Saying 5 x 3 = 15? [View all] pokerfan Oct 2015 OP

Why did they make it 5 x 3 and not 3 x 5? Rex Oct 2015 #1

Or give credit if a kid is smart enough to know that n * m = m * n and does the simpler computation karynnj Oct 2015 #6

No they didn't Egnever Oct 2015 #75

That is completely false -- 5 times 3 IS 3 times 5 by the commutative law - no matter how many karynnj Oct 2015 #103

and according to the order of operations Egnever Oct 2015 #107

No according to anything many many generations of students learned karynnj Oct 2015 #114

but failed reading comprehension? Egnever Oct 2015 #122

I have a graduate degree in Applied Mathematics karynnj Oct 2015 #129

Again reading comprehension fail Egnever Oct 2015 #130

ONLY given the method used to teach it karynnj Oct 2015 #134

Ok but the question wasn't are they equal. Egnever Oct 2015 #135

"should" defined by an arbitrary definition from the people who developed this way of teaching nt karynnj Oct 2015 #139

false choice, its not one or the other youceyec Oct 2015 #462

Eh, the kid was right about the math but did the teaching strategy in a different order. Chathamization Oct 2015 #168

Some of us who went on to get both undergraduate and graduate degrees in math Ms. Toad Oct 2015 #177

There is only one operation here - the child wrote it entirely correctly. Yo_Mama Oct 2015 #450

3x5 and 5x3 are mathmatically interchangable. Adrahil Oct 2015 #219

Does syntax matter? Renew Deal Oct 2015 #275

What the kid wrote corresponds to the most common axioms used for integer multiplication Chathamization Oct 2015 #285

I don't think so. Adrahil Oct 2015 #305

Not in this case, no. This problem doesn't have a syntax. Yo_Mama Oct 2015 #451

The commutative property of mathematics is not the concept being tested in the quiz. MohRokTah Oct 2015 #302

It's a stupid fucking test. Adrahil Oct 2015 #306

^^This^^ Gormy Cuss Oct 2015 #321

Algebra never made a bit of sense to me. Aerows Oct 2015 #411

Basic law of algebra is that addition and multiplication are order insensitive five added three time Monk06 Oct 2015 #155

Operational calculus requires proper order of operation. eom MohRokTah Oct 2015 #158

Quite correct. Adrahil Oct 2015 #308

Well I barely made it through Calculus 101 so there you go. Still don't understand this strategy vs Monk06 Oct 2015 #360

Thank goodness that everyone Aerows Oct 2015 #413

Yes, and any order is the proper order in multiplication/addition. n/t Yo_Mama Oct 2015 #455

OK--what's purple and commutes? eridani Oct 2015 #463

Apparently the repeated addition strategy is to take the right-hand number KamaAina Oct 2015 #2

But that rigidity obfuscates the fact that multiplication and addition are commutative pokerfan Oct 2015 #19

If only the kid had pointed that out KamaAina Oct 2015 #20

Or a D. hifiguy Oct 2015 #48

"New math" apparently means "arbitrary math" lumberjack_jeff Oct 2015 #26

But mathematically those things are IDENTICAL. Adrahil Oct 2015 #41

Exactly! Rex Oct 2015 #65

Not identical, just equal in their summation npk Oct 2015 #176

Beat me to it! Of course... TreasonousBastard Oct 2015 #194

Here's the thing... Adrahil Oct 2015 #212

Here's the other hing... TreasonousBastard Oct 2015 #225

I'm saying it doesn't matter... Adrahil Oct 2015 #236

I have an engineering brain, too Aerows Oct 2015 #422

what a horrible math teacher. youceyec Oct 2015 #461

3x5=5x3. Adrahil Oct 2015 #208

So, the problem here is "five multiplied by three" muriel_volestrangler Oct 2015 #210

This is addition/multiplication rather than subtraction/division. Yo_Mama Oct 2015 #452

Getting the rows/columns of a matrix right is NOT "just plain stupid". gcomeau Oct 2015 #393

But that negates the purpose of teaching this way!!!! Yo_Mama Oct 2015 #453

It could be that the teacher wanted the kid to show both ways of solving it. (nt) LostOne4Ever Oct 2015 #3

If the teacher wanted the kid to show both ways of solving it meow2u3 Oct 2015 #108

Probably because she told them what was expected from that type of problem in class nt LostOne4Ever Oct 2015 #128

The teacher subtracted a point from the score for using the 'wrong' way (nt) muriel_volestrangler Oct 2015 #211

The picture is the only clue we have LostOne4Ever Oct 2015 #343

No, the teacher wanted the kid to solve it in the way she did it (shown in purple). LisaL Oct 2015 #335

And we know that how? LostOne4Ever Oct 2015 #345

Because she showed it in purple right there on the sheet. LisaL Oct 2015 #350

Or that could be the other half of the problem she wanted LostOne4Ever Oct 2015 #352

No, it couldn't be. LisaL Oct 2015 #354

Why couldn't it be? LostOne4Ever Oct 2015 #356

Just read the instructions for repetead addition they are giving to kids. LisaL Oct 2015 #358

Again, that does not in anyway exclude my explanation LostOne4Ever Oct 2015 #363

The question doesn't say anything about solving the problem both ways. LisaL Oct 2015 #366

Nor does it say anything about not solving it both ways. It does show that the kid got half credit. LostOne4Ever Oct 2015 #371

I can't explain it to you any more than what I already did. LisaL Oct 2015 #372

That is because, you are making inductive conclusions without enough support to do so LostOne4Ever Oct 2015 #373

It's explained in the OP article as to what this teacher was looking for. LisaL Oct 2015 #374

The article says: LostOne4Ever Oct 2015 #375

Ask yourself these questions: LostOne4Ever Oct 2015 #378

Test had 3 questions, 2 points each. LisaL Oct 2015 #379

Easy, because Problem 3 didn't ask for a method and you can't see the bottom of problem 3 LostOne4Ever Oct 2015 #381

If each question had two parts, then it woud have had two parts. LisaL Oct 2015 #382

I already addressed that. Now about the questions I asked you? nt LostOne4Ever Oct 2015 #383

because the question asks for the application of a specific algorithm for computing Warren Stupidity Oct 2015 #4

But the kid did show 5 + 5 +5 - so he/she was not using memorization nt karynnj Oct 2015 #9

And the algorithm used 3+3+3+3+3 Warren Stupidity Oct 2015 #13

It's still rote memorization. Worse, it's rote memorization of an algorithm... lumberjack_jeff Oct 2015 #27

No - if he had just put the answer, it could be memorization karynnj Oct 2015 #29

Oh, GOD FORFEND that it be the dreaded MEMORIZATION!! WinkyDink Oct 2015 #39

If it doesn't answer the question, it's not the right answer. Donald Ian Rankin Oct 2015 #200

multiplication happens to be commutative but not all algorithms are Warren Stupidity Oct 2015 #213

If they're doing that, it genuinely does strike me as stupid. Donald Ian Rankin Oct 2015 #307

I'd love to make that teacher and her defenders learn to spell that way. "Spell 'CAT." "No, Johnny, WinkyDink Oct 2015 #359

I think you've missed the point. Donald Ian Rankin Oct 2015 #370

I know the exact point, and I think it is unnecessarily Jesuitical. "It's the ORDER." Yeah, yeah. WinkyDink Oct 2015 #403

The kid showed 5 three times (3x5), not 3 five times (5x3). Iggo Oct 2015 #47

It is the same thing. That's really the purpose of teaching this way. Yo_Mama Oct 2015 #456

I guess "repeated addition strategy" is not Commutative MowCowWhoHow III Oct 2015 #5

5x3=3x5. LisaL Oct 2015 #10

simplified, of course (and thats because regular multiplication is commutative) MowCowWhoHow III Oct 2015 #14

Which = STUPID. Are they trying to 'teach" that 3X5 does NOT equal 5X3?? It is CONDESCENDING to ask WinkyDink Oct 2015 #46

"I can use multiplication strategies to help me multiply" MowCowWhoHow III Oct 2015 #49

I could use an abacus, too, but if we are being REAL, NO KID will do this ridiculous step-by-step WinkyDink Oct 2015 #52

They could be conceptually preparing children for non-commutative multiplication MowCowWhoHow III Oct 2015 #53

The point is not to get the correct answer, Ms. Toad Oct 2015 #178

Many generations before this generation have done it either way and still ended up with liberal_at_heart Oct 2015 #183

Making sure a child understands the basic mathematical language Ms. Toad Oct 2015 #190

We are teaching our children if you just think this exact way I promise it will be so much easier liberal_at_heart Oct 2015 #193

No. We are teaching them a common language. Ms. Toad Oct 2015 #202

Have you given up the language of 'five multiplied by three', then? muriel_volestrangler Oct 2015 #220

The much more common way is 5 times 3. n/t Ms. Toad Oct 2015 #249

But saying 'multiplied by' still seems valid in the rest of the world muriel_volestrangler Oct 2015 #260

No one is removing multiplication from the vocabulary. Ms. Toad Oct 2015 #266

The teacher is removing it muriel_volestrangler Oct 2015 #290

But subtract 7 from 5 would NOT be the correct expression. Ms. Toad Oct 2015 #389

Grammatically, "5 multiplied by 3" is fine; and see the guide for teachers in #316 muriel_volestrangler Oct 2015 #394

There's nothing wrong with the phrase "multiplied by." Ms. Toad Oct 2015 #448

So, "5 multiplied by 3" means 5+5+5, doesn't it? muriel_volestrangler Oct 2015 #460

But that's not how multiplication is defined mathematically. In fact, the kid is probably closer to Chathamization Oct 2015 #217

That's different level of reasoning Ms. Toad Oct 2015 #247

But that's the point - the student is mathematically correct, but is marked down because they're not Chathamization Oct 2015 #271

It's not which order the teacher decides to use. Ms. Toad Oct 2015 #391

Counting the groups either way displays a knowledge of the process Gormy Cuss Oct 2015 #322

Have the child defend why their method works. Now that is teaching critical thinking! liberal_at_heart Oct 2015 #365

Correct, as to knowledge of the process. Ms. Toad Oct 2015 #385

Somewhere, an algebra teacher is screaming in agony. Yo_Mama Oct 2015 #454

No they are trying to teach order of operations Egnever Oct 2015 #79

What's the concept here? pokerfan Oct 2015 #205

5X3 means five groups of three. 3X5 means three groups of five. MohRokTah Oct 2015 #300

They no longer teach that multiplication is commutative? pokerfan Oct 2015 #355

What are these teachers preparing them for? LisaL Oct 2015 #346

I simply can't be bothered anymore. MowCowWhoHow III Oct 2015 #347

Bad teacher. Nye Bevan Oct 2015 #7

Having taught math for 11 years, Ms. Toad Oct 2015 #180

Then this approach is even more confusing... Adrahil Oct 2015 #214

Not all multiplication is communative. jeff47 Oct 2015 #244

Yeah... no matrix math involved here. No cross products or dot products. Adrahil Oct 2015 #246

Then stop arguing in favor of muddying it. jeff47 Oct 2015 #248

It doesn't ONLY mean that... Adrahil Oct 2015 #251

Yes, it does ONLY mean that. jeff47 Oct 2015 #258

Well said Egnever Oct 2015 #314

No, "five multiplied by three" does not 'literally' mean "add 5 threes together" (nt) muriel_volestrangler Oct 2015 #262

By all means, keep the real meaning a secret only known to yourself. (nt) jeff47 Oct 2015 #265

'five multiplied by three' means 'add a five to a five, and add a third five' muriel_volestrangler Oct 2015 #288

No, that's 3x5. jeff47 Oct 2015 #291

No, muriel is correct. 5x3 is closer to meaning 5+5+5 than 3+3+3+3+3 by most definitions of integer Chathamization Oct 2015 #295

The first number is the number of addends, the second is the addend. jeff47 Oct 2015 #296

But that's not true, it's usually defined in the opposite way. Look at how multiplication is defined Chathamization Oct 2015 #297

Yes, it is true. jeff47 Oct 2015 #301

So, that say that, also, "3 x 4 = 3 + 3 + 3 + 3 = 12" muriel_volestrangler Oct 2015 #309

Yes, because it is wrong for the same reason. jeff47 Oct 2015 #311

So why did you link to it? muriel_volestrangler Oct 2015 #315

If you read the article, you'd see that they were talking about communative property at that point. jeff47 Oct 2015 #339

I can't see "given that the second number is the addend" in the question muriel_volestrangler Oct 2015 #344

Eh, did you read the link? The axioms are closer to what the kid wrote than what you are claiming Chathamization Oct 2015 #323

The point is to not have to rip out shortcuts later that do not really help. jeff47 Oct 2015 #340

Again, did you read your link? What the kid put is closer to the axiomatic definition than what you Chathamization Oct 2015 #341

What shortcuts? LisaL Oct 2015 #342

Not at all. Ms. Toad Oct 2015 #264

Because they didn't follow the written directions frazzled Oct 2015 #8

Kid showed his work. He didn't memorize the table. LisaL Oct 2015 #12

It has been my experience that there is no winning this argument. Warren Stupidity Oct 2015 #15

most people read the article, like 11x27 , or 120x21 snooper2 Oct 2015 #18

If the teacher was trying to teach kids to do mental math, the kid was right. lumberjack_jeff Oct 2015 #37

Yes, the child understood the nature of the algorithm and found the simplest application of it Fumesucker Oct 2015 #45

You missed the point, and apparently didn't read the article. Ms. Toad Oct 2015 #181

Or you do it in your head 1939 Oct 2015 #204

Right. In the same way 99*1 means add 1, 99 times. lumberjack_jeff Oct 2015 #30

Exactly. The teacher would rather the kids sat there adding 1, 99 times, then LisaL Oct 2015 #54

You're focusing on the answer. Ms. Toad Oct 2015 #182

Wow! You're talking to a wall... TreasonousBastard Oct 2015 #197

I Think Everybody Sees RobinA Oct 2015 #224

I am not privy to what is going on in that calss except... TreasonousBastard Oct 2015 #226

'more inquiry' like "why did you deduct a point for the correct repeated addition I did?" muriel_volestrangler Oct 2015 #228

Not in Base Six. ChairmanAgnostic Oct 2015 #223

Yes that is true. Warren Stupidity Oct 2015 #230

The teacher is not thinking of what it means and doing the obvious rote thing. karynnj Oct 2015 #32

No the concept is order of operations not multiplication Egnever Oct 2015 #80

Yeah RobinA Oct 2015 #69

are you seriously defending this BS? Fast Walker 52 Oct 2015 #78

By all means, let's teach conformity rather than, ya know, math. Nt Adrahil Oct 2015 #215

How could Julie afford to buy 7 packages of cupcakes ???????? olddots Oct 2015 #11

I suggest she knock over a liquor store Warpy Oct 2015 #16

Winner! smirkymonkey Oct 2015 #55

Depends on how fast the cupcakes were traveling. Lochloosa Oct 2015 #17

She worked for a 100 hours making $2 per hour. LisaL Oct 2015 #348

Completely idiotic FiveGoodMen Oct 2015 #21

because as a professional Enrique Oct 2015 #22

And that teacher was wrong. Nye Bevan Oct 2015 #25

those things are loosely true Enrique Oct 2015 #35

But it DOESN'T matter, not for the discipline and not in real life. WinkyDink Oct 2015 #43

It absolutely does matter Egnever Oct 2015 #84

IT MATTERS MORE THAN THE ANSWER BEING 15!!!!!!!! MohRokTah Oct 2015 #118

Actually I failed operational calculus years later... Chan790 Oct 2015 #233

and why some of us "still" don't get it Horse with no Name Oct 2015 #428

And this "professional teacher" is wrong about what is important. Nye Bevan Oct 2015 #44

The lesson was order of operations, not multiplication. MohRokTah Oct 2015 #119

Even if that were the true lesson...the teacher is still the one that is wrong. Chan790 Oct 2015 #245

IT may be that to you, but it is incorrect from an operational order standpoint. MohRokTah Oct 2015 #250

For someone who is consistently wrong in proveable ways... Chan790 Oct 2015 #255

And with your lastest stalking insult, good bye. eom MohRokTah Oct 2015 #257

No, it doesn't. Iggo Oct 2015 #51

I think you and the teacher in question would get along very well (nt) Nye Bevan Oct 2015 #57

No it doesn't Egnever Oct 2015 #76

It teaches the student to respect the power structure, and that school isn't intended for him. n/t lumberjack_jeff Oct 2015 #31

I get it. prayin4rain Oct 2015 #294

Teachers are evaluated on a rigid set of standards Ex Lurker Oct 2015 #23

Bingo! I don't blame the teachers. I blame the government for privatizing our public liberal_at_heart Oct 2015 #186

Two words romanic Oct 2015 #24

exactly. Common Core. In other words, every child must think the exact same way liberal_at_heart Oct 2015 #198

The test says they're looking for specific multiplication strategies, not answers gollygee Oct 2015 #28

To most children, getting an answer marked wrong is negative reinforcement: punishment. pnwmom Oct 2015 #33

Stupid math. B Calm Oct 2015 #34

Is there any wonder why cash registers automatically count and dispense change now? world wide wally Oct 2015 #36

It's weird that they no longer have kids memorize multiplication tables Marrah_G Oct 2015 #111

1.) Because the teacher is a moron; 2.) Because of the order of the equation; 3.) Because math edu- WinkyDink Oct 2015 #38

+1 Gidney N Cloyd Oct 2015 #136

There is a conceptual difference between adding three copies of five and adding five copies of three struggle4progress Oct 2015 #40

You are not speaking of arithmetic but of higher mathematics. WinkyDink Oct 2015 #50

Dunno. It depends on what one wants to teach. The usual hand arithmetic with Arabic numerals struggle4progress Oct 2015 #63

"I'm not sure I'd take off for something like this in third grade, though"-- you think? Fast Walker 52 Oct 2015 #81

I didn't say I wouldn't -- I said I wasn't sure I would struggle4progress Oct 2015 #112

Maybe the teacher took into account the child's answer on question 2? retread Oct 2015 #42

Because the student did not give the answer required by the question. Agnosticsherbet Oct 2015 #56

Q. Solve 5x3 by repetitive addition. A. 5+5+5=15. Nye Bevan Oct 2015 #58

The student gave the wrong answer. Agnosticsherbet Oct 2015 #59

This is a weird and disheartening thread. (nt) Nye Bevan Oct 2015 #60

Ya Got That Right nt RobinA Oct 2015 #71

Agree. n/t lumberjack_jeff Oct 2015 #163

Evidently you have to start with the number on the right hand side. Rex Oct 2015 #67

And any teacher who insists on that is a moron (nt) Nye Bevan Oct 2015 #68

Or is trying to teach order of operations correctly from the start Egnever Oct 2015 #82

Again. Weird. Disheartening. (nt) Nye Bevan Oct 2015 #85

it's wierd that you don't get it and also I would say somewhat disheartening Egnever Oct 2015 #88

Now You're Being Ridiculous ProfessorGAC Oct 2015 #209

What has that got to do with the OP problem? muriel_volestrangler Oct 2015 #221

Neither weird nor disheartening. It does my heart good to see this taught in third grade. MohRokTah Oct 2015 #92

Mine as well Egnever Oct 2015 #106

It causes discomfort in parents because they were the victims of mathematics through rote. MohRokTah Oct 2015 #110

I agree completely Egnever Oct 2015 #115

Most of the nerds from my era discovered this stuff on their own. MohRokTah Oct 2015 #117

Yes it will. So much unlearning done later on. joshcryer Oct 2015 #159

And those of my age group who were "geeks" figured out how the operations worked because... MohRokTah Oct 2015 #161

I think there's a gap between the parent -> teacher relationship. joshcryer Oct 2015 #162

Far too often the result of the beginnings of math being taught by elementary teachers Ms. Toad Oct 2015 #184

And hey I admit my gut reaction was "WTF?" joshcryer Oct 2015 #187

Why bother to teach order of operations for situations where it makes no difference? eridani Oct 2015 #466

This is taken out of context. It's obviously array multiplication. joshcryer Oct 2015 #165

Ya know, I am suddenly reminded of my old HP calculator uising RPN... TreasonousBastard Oct 2015 #199

RPN certainly required fewer button pushes. eom MohRokTah Oct 2015 #304

5x3 is 33333's or three five times. 3x5 is 555's or five three times. JanMichael Oct 2015 #100

Speaking as the parent of a 7 year old EarlG Oct 2015 #61

Which Is Why RobinA Oct 2015 #72

So they should get full credit for doing the problem wrong? alarimer Oct 2015 #137

Attitudes like yours taught me to hate school and bureaucrats in the 2nd grade. Throd Oct 2015 #138

I Was In This Boat RobinA Oct 2015 #234

So how did so many generations before this one get by one doing it both ways? liberal_at_heart Oct 2015 #185

They are not even training people to be worker bees. LisaL Oct 2015 #334

Aren't you assuming that there were only three questions pokerfan Oct 2015 #195

It's not an assumption. MohRokTah Oct 2015 #240

All we know is that there were at least three questions (nt) pokerfan Oct 2015 #351

Math Does Have Rules RobinA Oct 2015 #227

Exactly. A totally made up rule that makes no sense. LisaL Oct 2015 #329

Oh, please. "Credit for the right method" is a farce designed SOLELY to give "partial credit" to the WinkyDink Oct 2015 #361

"the expected answer was 3+3+3+3+3" - that's conformity and rote memorization muriel_volestrangler Oct 2015 #222

Why do they talk about getting a point off like it is a punishment? Zing Zing Zingbah Oct 2015 #62

Because smart kids who come up with smart strategies to get to the correct answer Nye Bevan Oct 2015 #66

I don't agree with taking to the internet Zing Zing Zingbah Oct 2015 #70

The strategy was incorrect and displayed a misunderstanding of the order of operations. MohRokTah Oct 2015 #97

NEW MATH!!!! As a former .. Whiskeytide Oct 2015 #64

So... RobinA Oct 2015 #73

All I know is what I read. Whiskeytide Oct 2015 #93

Really great point, thanks for sharing Zing Zing Zingbah Oct 2015 #267

Because it's wrong? Egnever Oct 2015 #74

Really, really important to teach that 3 times 5 is different from 5 times 3. Nye Bevan Oct 2015 #83

Really important to teach the correct order of operations. Egnever Oct 2015 #86

Yes, order of operations is SO important in equations with one single operation. (nt) Nye Bevan Oct 2015 #87

So you just don't like when they start teaching it then. Egnever Oct 2015 #90

Nope, the kid got it right and the teacher is a moron (nt) Nye Bevan Oct 2015 #91

No, the kid got the order of operations incorrect and the teacher corrected them. MohRokTah Oct 2015 #95

Order doesn't matters since 5x3=3x5. LisaL Oct 2015 #141

This quiz was not about multiplication and final answers, it was about the order of operations and MohRokTah Oct 2015 #144

Order of operations makes no difference whatsoever in the particular problem the child was supposed LisaL Oct 2015 #147

Order of operations is CRITICAL in understanding how mathematics works. MohRokTah Oct 2015 #151

Apparently it was a quiz on drawing. WinkyDink Oct 2015 #368

EXACTLY!!!! MohRokTah Oct 2015 #94

Were You Ever RobinA Oct 2015 #237

Ye I was. I have an eidatic memory. MohRokTah Oct 2015 #239

teacher is correct. PowerToThePeople Oct 2015 #77

The answer was not marked wrong, 1 of 2 potential points was deducted on that and the next problem. MohRokTah Oct 2015 #89

5x3 = 5+5+5 = 15 (nt) Nye Bevan Oct 2015 #96

Incorrect. You reversed the proper order of operations. MohRokTah Oct 2015 #98

You would fit in very well as a math teacher at that school (nt) Nye Bevan Oct 2015 #99

That's because I understand the quiz was not about multiplication. MohRokTah Oct 2015 #101

And he will fondly look back upon the day he was docked a point for 5x3=5+5+5=15 (nt) Nye Bevan Oct 2015 #102

Correct, because his answer was only half correct (the "15" part, not the operational part). eom MohRokTah Oct 2015 #105

And in the real world, people don't give a shit how he got there. Throd Oct 2015 #132

And in the real world, people who don't give a shit how they get there serve fries and burgers... MohRokTah Oct 2015 #145

How exactly all these people became scientists and engineers before being taught this way? LisaL Oct 2015 #146

They either figured out how operational order functioned in mathematics upon reaching algebra MohRokTah Oct 2015 #149

They unlearned stuff they learned in grade school. joshcryer Oct 2015 #160

I seem to be making a pretty good living in the real world. Throd Oct 2015 #269

Are you a scientist? MohRokTah Oct 2015 #270

No, I am not a scientist. Throd Oct 2015 #272

Based upon what you do,... MohRokTah Oct 2015 #287

If this kid wants a job in STEM and is going to take calculus Goblinmonger Oct 2015 #353

However did we manage before? Throd Oct 2015 #388

Maybe we'll get more kids into STEM. Goblinmonger Oct 2015 #392

Poorly Goblinmonger Oct 2015 #433

Except this isn't what multiplication means. N/T Chathamization Oct 2015 #407

They are clearly teaching more than just multiplication. Goblinmonger Oct 2015 #432

So you teach a third grader something incorrect about multiplication with the aim that years later Chathamization Oct 2015 #435

The question wasn't "What is 5x3?" Goblinmonger Oct 2015 #436

What? A 5x3 matrix is not equal to 3+3+3+3+3, and it doesn't equal 15. If you wrote Chathamization Oct 2015 #438

The answer to the question asked is: Goblinmonger Oct 2015 #439

Yes, it's about arbitrary strategies that are being taught and not about math. If you want to test Chathamization Oct 2015 #441

4 out 6 on a quiz would be a D oberliner Oct 2015 #191

Exactly. Something like this should be where they mark it right, but leave a note of "By the way..." Zynx Oct 2015 #261

Either way is correct. LisaL Oct 2015 #330

raise your hand if you've ever drawn an array to model basic multiplication... Takket Oct 2015 #104

I have no idea what that even means Marrah_G Oct 2015 #113

I used to do it for fun. MohRokTah Oct 2015 #121

Not me. LisaL Oct 2015 #167

And we wonder why children get frustrated and fall through the cracks. Marrah_G Oct 2015 #109

You could not be more wrong. MohRokTah Oct 2015 #116

I disagree Marrah_G Oct 2015 #120

This is the very basis of operational calculus. MohRokTah Oct 2015 #123

Have a nice night Moh :) Marrah_G Oct 2015 #124

Good to see I'm not the only one who thinks Nye Bevan Oct 2015 #125

the shortcuts are fine ibegurpard Oct 2015 #174

I can't help but wonder how we managed to get somewhere in science without having to learn this way. LisaL Oct 2015 #140

Honestly? We didn't. MohRokTah Oct 2015 #142

We don't need twice as many scientists. LisaL Oct 2015 #148

I agree, twice as many are nowhere near enough. We need to turn out about ten times as many as we MohRokTah Oct 2015 #150

Oh, Come On RobinA Oct 2015 #241

The kid in the article didn't, as is true of at least half of the people posting in this thread. eom MohRokTah Oct 2015 #242

As a broader policy question, what exactly would we do with five times as many scientists? Zynx Oct 2015 #263

There is not much for them to do here either. LisaL Oct 2015 #336

They don't want thinkers. They want workers, workers that do what they are told liberal_at_heart Oct 2015 #179

Because they didn't follow instructions? jazzimov Oct 2015 #126

5x3 = 5+5+5 = 15. The horror (nt) Nye Bevan Oct 2015 #131

Half right. You failed to properly apply the repeated addition strategy. MohRokTah Oct 2015 #153

If you get the answer right, I don't care how you got there. Throd Oct 2015 #127

They failed to get the answer right because they failed to properly apply the repeated addition... MohRokTah Oct 2015 #154

Kid propertly applied the repeated addition, got the correct answer, and used an easier way to solve LisaL Oct 2015 #338

the point of this question ibegurpard Oct 2015 #171

LOOK AT QUESTION 3!!! GummyBearz Oct 2015 #133

Question 3 was a combination of an array and operational order. MohRokTah Oct 2015 #156

You will also notice GummyBearz Oct 2015 #166

yeah..I like it, you're testing for those that read the article versus those that react viscerally Demonaut Oct 2015 #143

I read the article. I still think it's bullshit. liberal_at_heart Oct 2015 #188

Same here.... Adrahil Oct 2015 #216

I get why. It's five threes not three fives. bravenak Oct 2015 #152

Welcome back, bravenak! nt tblue37 Oct 2015 #169

Thank you! bravenak Oct 2015 #170

This shit just confuses a young kid. U4ikLefty Oct 2015 #157

I tend to agree Skittles Oct 2015 #172

They're teaching array multiplication. Row/object. joshcryer Oct 2015 #164

Hich is still bullshit... Adrahil Oct 2015 #218

No it can't Goblinmonger Oct 2015 #395

part of math ibegurpard Oct 2015 #173

#2 is correct. Array of 4 columns of 6. Why wrong? madfloridian Oct 2015 #175

Same thing as in question one (according to the new math instructions). LisaL Oct 2015 #386

I taught new math the first time they threw it at the kids. madfloridian Oct 2015 #387

Yes, luckily these ideas come and go. I can't wait til it goes. liberal_at_heart Oct 2015 #445

Will future generations of engineers have the creativity to solve problems if they are liberal_at_heart Oct 2015 #189

Isn't think teaching them three different ways? Renew Deal Oct 2015 #278

What madfloridian said caraher Oct 2015 #192

Just be happy the question pokerfan Oct 2015 #196

It's true that it can be convention. joshcryer Oct 2015 #206

I learned how to roll a joint with one hand in art school olddots Oct 2015 #201

Because the teacher doesn�t understand math Kuroneko Oct 2015 #203

Yeah, some of the claims here are bizarre. Chathamization Oct 2015 #276

But there's an incongruity with the scientific discovery process here. BadgerKid Oct 2015 #207

Theoretical physicist here. I have my doubts that this is a good way to teach math. redgreenandblue Oct 2015 #229

Well, Give That RobinA Oct 2015 #243

Exactly. When a bright kid clearly grasps the commutativity of multiplication, and shrewdly uses it Nye Bevan Oct 2015 #254

I agree Marrah_G Oct 2015 #259

It's not a good way to teach math. LisaL Oct 2015 #331

Thank you for that well thought response. I had a math professor who jokingly told us one time that liberal_at_heart Oct 2015 #376

Algorithms are typically guaranteed to work for every case of a certain class of problems. redgreenandblue Oct 2015 #459

Stuff like this is what turns kids off from math n2doc Oct 2015 #231

The kid didn't solve it the way the teacher wanted it to be solved. Deadshot Oct 2015 #232

I've never liked the Martinet School of Teaching Methods. "Put your NAME here, the TITLE there." WinkyDink Oct 2015 #253

Yes, he solved it in easier way and correctly. LisaL Oct 2015 #333

It's not about being right. Deadshot Oct 2015 #447

1. What was the objective? LWolf Oct 2015 #235

^^^ This. Iggo Oct 2015 #283

It is the objective that we take issue with. liberal_at_heart Oct 2015 #369

You take issue LWolf Oct 2015 #443

I object to children not being allowed to use different methods and being told they can only liberal_at_heart Oct 2015 #446

I didn't think I could hate math any more than I already do. a la izquierda Oct 2015 #238

I took math including Calculus. Still have no affinity for cold numbers, and prefer poetry. Sue me. WinkyDink Oct 2015 #252

High school English teacher. Give me some Whitman. Goblinmonger Oct 2015 #397

"Friday Night Lights": It's not just for Texas anymore. WinkyDink Oct 2015 #402

Many of the responses in this thread illustrate why the clock kid got into trouble. Nye Bevan Oct 2015 #256

The important thing is that we must never question Common Core Orrex Oct 2015 #268

Do you have any actual evidence this was related to Common Core? Recursion Oct 2015 #274

My kids have had do exactly that kind of bullshit math Orrex Oct 2015 #280

And, again, the relation to Common Core is? Recursion Oct 2015 #282

Well, that's a straight up lie. Orrex Oct 2015 #286

This message was self-deleted by its author Recursion Oct 2015 #289

Let me try to be nicer: no, you're wrong Recursion Oct 2015 #292

Really? Orrex Oct 2015 #298

Yep. Now read those links Recursion Oct 2015 #299

Sure. Let's see links to all the times you've called them a scam. Orrex Oct 2015 #310

So, just to be clear, you are confident that you know better than a professional teacher? Recursion Oct 2015 #273

In every school there are great teachers, average teachers and awful teachers. Nye Bevan Oct 2015 #284

In addition Orrex Oct 2015 #337

We also have no idea what method the teacher did or didn't teach Recursion Oct 2015 #458

This is a professional, stupid teacher. This is appalling. n/t Yo_Mama Oct 2015 #457

I recall a story sarisataka Oct 2015 #277

I'm 64 and still remember getting an "F" on a 4th grade math test. mnhtnbb Oct 2015 #279

I was one of those kids too Marrah_G Oct 2015 #377

Well I had mostly As. But then I was never taught this way. LisaL Oct 2015 #437

Very simple. A math-teacher who doesn't know math? Fire him. DetlefK Oct 2015 #281

What? No no no. Recursion Oct 2015 #303

The teacher is punishing the kid for failing to conform to the stupid convention. backscatter712 Oct 2015 #293

"punishing" Blue_Adept Oct 2015 #313

I've read this thread several times today Blue_Adept Oct 2015 #312

Let me show you a rule in mathematics muriel_volestrangler Oct 2015 #316

I've seen your other posts in the thread Blue_Adept Oct 2015 #317

'It'? What's 'it'? The only singular noun you used before 'it' was 'thread' muriel_volestrangler Oct 2015 #318

Basically Blue_Adept Oct 2015 #319

What was that you said about 'the "my special snowflake" mentality'? muriel_volestrangler Oct 2015 #320

If you are preparing them for advanced algebra Goblinmonger Oct 2015 #398

Do you use the phrase 'multiplied by'? Do you feel it hinders advanced algebra and calculus? muriel_volestrangler Oct 2015 #423

English teacher with two years in civil engineering education. Goblinmonger Oct 2015 #434

The first question is about the repeated addition strategy muriel_volestrangler Oct 2015 #440

Why don't you just read the manual? LisaL Oct 2015 #327

Thanks. This guide was issued in 2001. So apparently back then LisaL Oct 2015 #325

Also look on page 4 of the manual. LisaL Oct 2015 #328

If you want to solve the problem of 5x3 by repetative addition, LisaL Oct 2015 #326

One of the basic fundamental rules of math is that LisaL Oct 2015 #332

What you are reading, to be precise, are posts by those of us who did JUST FINE in the 50's/60's. WinkyDink Oct 2015 #367

So math is not about giving them the option of a career based on math Goblinmonger Oct 2015 #399

It appears we have a lot of anti-math people here PowerToThePeople Oct 2015 #465

Oh, yes! "Non-intellectuals" = "Non-math people," idiots like philosophers, Pulitzer winners, etc. WinkyDink Oct 2015 #471

You are unable to say "five multiplied by three" is a way to say '5x3' muriel_volestrangler Oct 2015 #475

That's funny I was thinking your posts calling children "special snowflakes" sounded an awful liberal_at_heart Oct 2015 #482

I don't know how I feel about this. Xyzse Oct 2015 #324

Problem with shortcuts is BadgerKid Oct 2015 #349

That's precisely the point. Xyzse Oct 2015 #362

I would have answered same way as the kid. MadrasT Oct 2015 #357

Even in 3rd grade, were that I, I'd have laughed in the teacher's face. Might have said "PO-TAH-TO." WinkyDink Oct 2015 #364

This thread will go down as "The great Math Wars" BlueJazz Oct 2015 #380

It's more than math wars. It is the war between those who see Race to the Top and liberal_at_heart Oct 2015 #383

I'm not sure you wrote those points in the correct order. ;-) WinkyDink Oct 2015 #404

1.The teacher did not punish. 2.The child answered incorrectly. 3.The child earned that grade. Glassunion Oct 2015 #390

My husband and I were talking about this thread at dinner tonight. mnhtnbb Oct 2015 #396

It does if you are preparing for calculus Goblinmonger Oct 2015 #400

In 3rd grade? Really? Turn off a kid to math at this age and there will be no need mnhtnbb Oct 2015 #401

The kid lost two points on a homework assignment. Goblinmonger Oct 2015 #430

Well, clearly some math teachers somewhere in the world know what they are doing mnhtnbb Oct 2015 #464

Whoa! Preparing for Keanu Reeves? Cool! WinkyDink Oct 2015 #406

Clever. Goblinmonger Oct 2015 #431

This message was self-deleted by its author Orrex Oct 2015 #483

But THAT, mon ami, is THE CRUX: Some argue the METHOD counts most; some, the correct answer. WinkyDink Oct 2015 #405

Yes, math is based on rules of math (directions) PowerToThePeople Oct 2015 #408

I'd say that using a particular method can be pretty important, but this thread shows the serious Chathamization Oct 2015 #409

five times three is 3+3+3+3+3 PowerToThePeople Oct 2015 #410

But that's not true. See reply 323. If the people who have taken graduate level math courses are Chathamization Oct 2015 #412

they are NOT learning commutative property in 3rd grade PowerToThePeople Oct 2015 #415

Well, like I said, even if you want to ignore the commutative property the kids answer is closer to Chathamization Oct 2015 #418

well PowerToThePeople Oct 2015 #421

They're wrong based upon axiomatic definitions of multiplication that can be found in, for example, Chathamization Oct 2015 #425

How would you write 'five multiplied by three'? (nt) muriel_volestrangler Oct 2015 #414

that was not the question asked. PowerToThePeople Oct 2015 #416

I think it was. Did you think the question asked was 'three multiplied by five'? (nt) muriel_volestrangler Oct 2015 #417

the question was "5x3=" (n/t) PowerToThePeople Oct 2015 #419

You say that is not 'five multiplied by three'. I (and the guide in #316) say it is. muriel_volestrangler Oct 2015 #420

Please tell me you are not serious. 5x3 cannot be interpreted as 5 multiplied by 3? liberal_at_heart Oct 2015 #444

I work in a highly technical field. Aerows Oct 2015 #424

Practical application MATTERS. PowerToThePeople Oct 2015 #426

I can only speak for myself Aerows Oct 2015 #429

One of the problems with teaching that only way is correct is that people learn, see, and liberal_at_heart Oct 2015 #442

Theory's important too, but apparently a lot of the people pushing it don't understand it Chathamization Oct 2015 #427

The child understands the material better than the teacher!!!! Yo_Mama Oct 2015 #449

Wow, some textbook authoritarianism in this thread. redgreenandblue Oct 2015 #467

Yes, there seems to be a very loud faction here on DU who can't help but tell people liberal_at_heart Oct 2015 #481

I'd say quibbling over a point because a teacher can, exemplifies a person in a position that should lonestarnot Oct 2015 #468

Hey helicopter parent, your little snowflake got it wrong. PowerToThePeople Oct 2015 #469

Even if the concession is made that the child didn't follow instructions but went instead for the WinkyDink Oct 2015 #470

That answer isn't just bizarre to a third grader, but to anyone with a decent grasp of math Chathamization Oct 2015 #473

There is no concession to do as the student answer is correct. Kuroneko Oct 2015 #476

You seem not to know the phrase "Even if....." WinkyDink Oct 2015 #484

Here's a fun reductio ad absurdim way to think of it: Orrex Oct 2015 #472

That is absurdim PowerToThePeople Oct 2015 #474

You find math to be humiliating? That's bizarre. Orrex Oct 2015 #480

I'll suppose in thirty years we'll find out whether or not this is all bullshit. Throd Oct 2015 #477

A math question for all in this thread. PowerToThePeople Oct 2015 #478

Where's Tom Lehrer when we need him? nt Buns_of_Fire Oct 2015 #479