General Discussion

Aerows

(39,961 posts)

413. Thank goodness that everyone

Thu Oct 22, 2015, 08:10 PM

Oct 2015

that has ever calculated physics wasn't quite so rigid. Word problems, calculating acceleration and volume was as easy as pie for me. Hell, when I was driving somewhere I used to do it in my head to calculate how many extra mph I could go and how much time it would save me. I kind of still do it.

"Orders of operation" and rigid crap like that drove me nuts. I can do tons useful things with math, geometry, calculus - I can't do a damn bit of anything with "orders of operation".

It's like defining that unless you arrived at the same answer with a different method means that the answer is invalid. Can you build a house without "orders of operation" but by knowing fundamental principles involved in the quadratic equation? Fundamental principles to cut the wood to achieve a certain angle?

Yes. You can.

How do you dig half of a hole?

With half a shovel. <--- That is orders of operation ideas.

It's meaningless.

Edit history

Please sign in to view edit histories.

Recommendations

0 members have recommended this reply (displayed in chronological order):

484 replies

= new reply since forum marked as read

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