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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]Nye Bevan
(25,406 posts)85. Again. Weird. Disheartening. (nt)
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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