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In reply to the discussion: Why Would a Math Teacher Punish a Child for Saying 5 x 3 = 15? [View all]Egnever
(21,506 posts)80. No the concept is order of operations not multiplication
Two entirely different concepts.
If the question was solve the equation he would have got it right but that was not the question.
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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
That is completely false -- 5 times 3 IS 3 times 5 by the commutative law - no matter how many
karynnj
Oct 2015
#103
"should" defined by an arbitrary definition from the people who developed this way of teaching nt
karynnj
Oct 2015
#139
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
What the kid wrote corresponds to the most common axioms used for integer multiplication
Chathamization
Oct 2015
#285
The commutative property of mathematics is not the concept being tested in the quiz.
MohRokTah
Oct 2015
#302
Basic law of algebra is that addition and multiplication are order insensitive five added three time
Monk06
Oct 2015
#155
Well I barely made it through Calculus 101 so there you go. Still don't understand this strategy vs
Monk06
Oct 2015
#360
But that rigidity obfuscates the fact that multiplication and addition are commutative
pokerfan
Oct 2015
#19
It could be that the teacher wanted the kid to show both ways of solving it. (nt)
LostOne4Ever
Oct 2015
#3
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
No, the teacher wanted the kid to solve it in the way she did it (shown in purple).
LisaL
Oct 2015
#335
Nor does it say anything about not solving it both ways. It does show that the kid got half credit.
LostOne4Ever
Oct 2015
#371
That is because, you are making inductive conclusions without enough support to do so
LostOne4Ever
Oct 2015
#373
Easy, because Problem 3 didn't ask for a method and you can't see the bottom of problem 3
LostOne4Ever
Oct 2015
#381
because the question asks for the application of a specific algorithm for computing
Warren Stupidity
Oct 2015
#4
It's still rote memorization. Worse, it's rote memorization of an algorithm...
lumberjack_jeff
Oct 2015
#27
I'd love to make that teacher and her defenders learn to spell that way. "Spell 'CAT." "No, Johnny,
WinkyDink
Oct 2015
#359
I know the exact point, and I think it is unnecessarily Jesuitical. "It's the ORDER." Yeah, yeah.
WinkyDink
Oct 2015
#403
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 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
Many generations before this generation have done it either way and still ended up with
liberal_at_heart
Oct 2015
#183
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
Have you given up the language of 'five multiplied by three', then?
muriel_volestrangler
Oct 2015
#220
But saying 'multiplied by' still seems valid in the rest of the world
muriel_volestrangler
Oct 2015
#260
Grammatically, "5 multiplied by 3" is fine; and see the guide for teachers in #316
muriel_volestrangler
Oct 2015
#394
But that's not how multiplication is defined mathematically. In fact, the kid is probably closer to
Chathamization
Oct 2015
#217
But that's the point - the student is mathematically correct, but is marked down because they're not
Chathamization
Oct 2015
#271
Have the child defend why their method works. Now that is teaching critical thinking!
liberal_at_heart
Oct 2015
#365
No, "five multiplied by three" does not 'literally' mean "add 5 threes together" (nt)
muriel_volestrangler
Oct 2015
#262
'five multiplied by three' means 'add a five to a five, and add a third five'
muriel_volestrangler
Oct 2015
#288
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
But that's not true, it's usually defined in the opposite way. Look at how multiplication is defined
Chathamization
Oct 2015
#297
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
Again, did you read your link? What the kid put is closer to the axiomatic definition than what you
Chathamization
Oct 2015
#341
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
'more inquiry' like "why did you deduct a point for the correct repeated addition I did?"
muriel_volestrangler
Oct 2015
#228
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
It teaches the student to respect the power structure, and that school isn't intended for him. n/t
lumberjack_jeff
Oct 2015
#31
Bingo! I don't blame the teachers. I blame the government for privatizing our public
liberal_at_heart
Oct 2015
#186
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
Is there any wonder why cash registers automatically count and dispense change now?
world wide wally
Oct 2015
#36
1.) Because the teacher is a moron; 2.) Because of the order of the equation; 3.) Because math edu-
WinkyDink
Oct 2015
#38
There is a conceptual difference between adding three copies of five and adding five copies of three
struggle4progress
Oct 2015
#40
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
Neither weird nor disheartening. It does my heart good to see this taught in third grade.
MohRokTah
Oct 2015
#92
It causes discomfort in parents because they were the victims of mathematics through rote.
MohRokTah
Oct 2015
#110
And those of my age group who were "geeks" figured out how the operations worked because...
MohRokTah
Oct 2015
#161
Far too often the result of the beginnings of math being taught by elementary teachers
Ms. Toad
Oct 2015
#184
Why bother to teach order of operations for situations where it makes no difference?
eridani
Oct 2015
#466
Ya know, I am suddenly reminded of my old HP calculator uising RPN...
TreasonousBastard
Oct 2015
#199
So how did so many generations before this one get by one doing it both ways?
liberal_at_heart
Oct 2015
#185
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
Because smart kids who come up with smart strategies to get to the correct answer
Nye Bevan
Oct 2015
#66
The strategy was incorrect and displayed a misunderstanding of the order of operations.
MohRokTah
Oct 2015
#97
Really, really important to teach that 3 times 5 is different from 5 times 3.
Nye Bevan
Oct 2015
#83
Yes, order of operations is SO important in equations with one single operation. (nt)
Nye Bevan
Oct 2015
#87
No, the kid got the order of operations incorrect and the teacher corrected them.
MohRokTah
Oct 2015
#95
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
The answer was not marked wrong, 1 of 2 potential points was deducted on that and the next problem.
MohRokTah
Oct 2015
#89
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 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
So you teach a third grader something incorrect about multiplication with the aim that years later
Chathamization
Oct 2015
#435
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
Yes, it's about arbitrary strategies that are being taught and not about math. If you want to test
Chathamization
Oct 2015
#441
Exactly. Something like this should be where they mark it right, but leave a note of "By the way..."
Zynx
Oct 2015
#261
I can't help but wonder how we managed to get somewhere in science without having to learn this way.
LisaL
Oct 2015
#140
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
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
They don't want thinkers. They want workers, workers that do what they are told
liberal_at_heart
Oct 2015
#179
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
yeah..I like it, you're testing for those that read the article versus those that react viscerally
Demonaut
Oct 2015
#143
Will future generations of engineers have the creativity to solve problems if they are
liberal_at_heart
Oct 2015
#189
Theoretical physicist here. I have my doubts that this is a good way to teach math.
redgreenandblue
Oct 2015
#229
Exactly. When a bright kid clearly grasps the commutativity of multiplication, and shrewdly uses it
Nye Bevan
Oct 2015
#254
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
I've never liked the Martinet School of Teaching Methods. "Put your NAME here, the TITLE there."
WinkyDink
Oct 2015
#253
I object to children not being allowed to use different methods and being told they can only
liberal_at_heart
Oct 2015
#446
I took math including Calculus. Still have no affinity for cold numbers, and prefer poetry. Sue me.
WinkyDink
Oct 2015
#252
Many of the responses in this thread illustrate why the clock kid got into trouble.
Nye Bevan
Oct 2015
#256
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
The teacher is punishing the kid for failing to conform to the stupid convention.
backscatter712
Oct 2015
#293
'It'? What's 'it'? The only singular noun you used before 'it' was 'thread'
muriel_volestrangler
Oct 2015
#318
What was that you said about 'the "my special snowflake" mentality'?
muriel_volestrangler
Oct 2015
#320
Do you use the phrase 'multiplied by'? Do you feel it hinders advanced algebra and calculus?
muriel_volestrangler
Oct 2015
#423
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
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
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
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
1.The teacher did not punish. 2.The child answered incorrectly. 3.The child earned that grade.
Glassunion
Oct 2015
#390
In 3rd grade? Really? Turn off a kid to math at this age and there will be no need
mnhtnbb
Oct 2015
#401
Well, clearly some math teachers somewhere in the world know what they are doing
mnhtnbb
Oct 2015
#464
But THAT, mon ami, is THE CRUX: Some argue the METHOD counts most; some, the correct answer.
WinkyDink
Oct 2015
#405
I'd say that using a particular method can be pretty important, but this thread shows the serious
Chathamization
Oct 2015
#409
But that's not true. See reply 323. If the people who have taken graduate level math courses are
Chathamization
Oct 2015
#412
Well, like I said, even if you want to ignore the commutative property the kids answer is closer to
Chathamization
Oct 2015
#418
They're wrong based upon axiomatic definitions of multiplication that can be found in, for example,
Chathamization
Oct 2015
#425
I think it was. Did you think the question asked was 'three multiplied by five'? (nt)
muriel_volestrangler
Oct 2015
#417
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
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
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
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
I'll suppose in thirty years we'll find out whether or not this is all bullshit.
Throd
Oct 2015
#477