http://www.aol.com/article/2015/10/26/why-5-5-5-15-is-wrong-under-the-common-core/21254219
http://www.businessinsider.com/why-55515-is-wrong-under-the-common-core-2015-10

Common Core says it is the second one.

What does TWW say? is 5x3 only equal to "5 groups of 3", or only "3 groups of 5", or both?

(Also see answer to the question after it in the pic below)

10/28/2015 8:39:26 PM

I think I saw a Facebook friend of mine ranting about this last week. That's right....you are posting shit a week after a Facebook mother got her info.


For shame.

10/28/2015 8:46:20 PM

AMERRICUUH FUCK YEAH

10/28/2015 8:52:49 PM

I say both, because I understand numbers, not some dumb ass common core bullshit

10/28/2015 8:54:30 PM

According to the commutative property 5x3 = 3x5
While I can understand the rational for the "common core" way of explaining the problem as a teaching tool, I would not expect one to lose a point on a quiz for this. As they are both correct.

As an engineer I'd be pissed if I learned my child lost a point for that as it shows the teachers lack of understanding of mathematics

10/28/2015 8:57:42 PM

Commutative Property of Multiplication, FTW!

Common Core, FTL!

10/28/2015 9:03:25 PM

Quote :

"While I can understand the rational for the "common core" way of explaining the problem as a teaching tool, I would not expect one to lose a point on a quiz for this. As they are both correct. As an engineer I'd be pissed if I learned my child lost a point for that as it shows the teachers lack of understanding of mathematics"

Fuck, I agree with HUR.

Some of the basic ideas behind common core are good (teaching the underlying concepts behind how and why mathematics work), but the implementation is sometimes insane and produces things like this. I've already read about how this was a grading error and not how common core is supposed to be taught and so on, so I'm not going to be too quick to judge this, but there is something to be said for rote memorization as well. Sometimes it isn't necessary to teach the underlying concepts until later if it's necessary.

I also would lose my shit if my kid brought this home. If we're trying to teach the fundamentals of how math works the commutative property had damn sure be one of the things we start with when we teach multiplication.

10/28/2015 9:34:12 PM

don't forget the 4x6 problem right under that...

10/28/2015 9:47:19 PM

or the one below that where, presumably, you would get marked off for just writing 7x4=28.

[Edited on October 28, 2015 at 9:58 PM. Reason : asdsad]

10/28/2015 9:50:49 PM

This has nothing to do with common core, it's just probably bad teaching, which has been around forever.

10/28/2015 10:01:21 PM

Yup. At it's foundation common core makes sense. I remember, as I'm sure many of you do, playing with "number cubes" and similar things in elementary school to help people understand and conceptualize. For me it was kind of useless because I was always super good at math and didn't need the visual aids to understand that 100=10 units of 10 or 100 single units or 2 units of 50 and so on. For a lot of people though that helps them understand.

Common core math is trying to teach those underlying concepts. Parents are freeking out because it's different than how they learned it. Not surprisingly, conservative parents are especially freaked out because conservatives by definition hate and fear change.

10/28/2015 10:19:52 PM

But conceptually 5x3 is not the same as 3x5. You can do a lot heavier weight when you bench 5 sets of 3, but need to step down the weight when you bench 3 sets of 5.

This is an application for a personal trainer at a gym right? Cause otherwise this is just plain retarded.

10/28/2015 10:26:40 PM

whichever one is easier to add

10/28/2015 11:26:20 PM

Quote :

"But conceptually 5x3 is not the same as 3x5. You can do a lot heavier weight when you bench 5 sets of 3, but need to step down the weight when you bench 3 sets of 5."

conceptually 5x3 is identical to 3x5, once you start adding words to it you completely change the question. they're teaching multiplication not "sets".

10/28/2015 11:33:07 PM

The right answer doesn't even make sense if you were going to teach it this way. If you say out the problem it is: "five times three" or "five multiplied by three". Which implies five, three times. Never mind the fact that both methods are correct I don't know why you would teach the "correct" way to be 3+3+3+3+3

[Edited on October 28, 2015 at 11:41 PM. Reason : I didn't read the article linked first. you're taught to read it as "five groups of three"]

10/28/2015 11:38:06 PM

well, they just inverted the idea. don't know why. there's 5 threes. It's completely arbitrary. but whatever

[Edited on October 28, 2015 at 11:42 PM. Reason : ]

10/28/2015 11:41:56 PM

Quote :

""five times three" or "five multiplied by three". Which implies five, three times."

Five TIMES three mean you are taking something 5 times. So it implies, five threes, or three, five times.

10/28/2015 11:43:55 PM

right, it's both, hence the commutative property. x*y and y*x are conceptually the same

once you start talking about cupcakes in packages it changes, since you are assigning a hierarchy. the cupcakes are within the packages. you can only get the cupcakes in groups of 4.

[Edited on October 29, 2015 at 12:15 AM. Reason : er, commutative oops. I know I'm repeating. I agree with those who said it first. blah]

10/29/2015 12:04:04 AM

Quote :

"you're taught to read it as "five groups of three""

that's dumb though and probably leads to learning disabilities, on some rain man shit

10/29/2015 12:16:55 AM

I wonder what happens when these kids start to learn algebra? You gotta have an open mind to find solutions. I agree this seems like it would be a detriment.

10/29/2015 12:28:31 AM

people are like ants

I do not envy people who sit around mulling over things like this

10/29/2015 12:52:12 AM

I noticed the teacher took off a point on the question below because the kid made 6 horizontal rows of 4. But if read vertically it's 4 columns of 6 which would be correct by the teachers standard. Kind of illustrates the foolishness of the way the test was graded.

10/29/2015 1:25:48 AM

As a math teacher, I'm really sick of this kind of misinformation being passed around constantly. I know it's already been mentioned at least once in this thread, but

THIS HAS ABSOLUTELY NOTHING TO DO WITH COMMON CORE!!!!

Common core (CC) is just a set of standards; teachers are still free to choose for themselves how they wish to achieve the standards set by CC.

I'm also really bothered when I see people bitch about some of the methods supposedly used by CC. Lots of ignorant people complain, saying, "Why can't they just teach the old way!" They never even begin to realize that some of the methods they rail against are intended to develop an intuitive number sense in students (as opposed to mindlessly performing some algorithm). Whether these methods are successful at developing that number sense may be an open question, but something clearly isn't working in math education as it stands (from my perspective); I'd say a majority of my students don't have a good number sense, and this is at the university level.

One of my favorite stories: While I was at State, I was tutoring an undergrad; she required a calculator to do something like 16+1, got 18. She began to proceed with the rest of the problem like everything was fine; I stopped her and told her to try that again. This time she gets 17 and says, "That's weird; the calculator does that to me sometimes."

On the other hand, I think this example is ridiculous. I can't imagine any reason for preferring 5 x 3 as either five 3's or three 5's; either is fine as I'm concerned. I mean, it would be different if this was ordinal arithmetic where multiplication isn't commutative, but not elementary school multiplication.

10/29/2015 1:36:25 AM

Most of us (who aren't either teachers, or involved parents of kids) don't really understand Common Core because we're older.

But you're definitely right in your last sentence.

I have come to the conclusion that this math teacher is simply a fucking retard who should be fired for hindering this child's learning based on his or her own ridiculous syntax requirements

[Edited on October 29, 2015 at 2:58 AM. Reason : .]

10/29/2015 2:34:50 AM

god damn

Cabbage is fucking rustled

10/29/2015 4:49:47 AM

Quote :

"god damn Cabbage is fucking rustled "

nearly spit my coffee on the screen.

10/29/2015 6:57:29 AM

It is far more important that a student learn and understand that 5x3=3x5, rather than 5x3=3+3+3+3+3 instead of 5+5+5. One is semantics, one is math.

10/29/2015 9:32:31 AM

Your post us backwards, the second part is more important to learn because that's the concept of math, the first part is meaningless to someone who doesn't understand the second part.

The only issue here is preferring 5 groups of 3 to 3 groups of 5, but teaching groups like that isn't new and is how I was taught in public school in K with counting blocks then again in 1st grade

10/29/2015 9:48:38 AM

Look what you done; you done got my jimmies all rustled.

10/30/2015 12:17:53 PM

Kurtis636 said:

Quote :

"or the one below that where, presumably, you would get marked off for just writing 7x4=28."

And the teacher would be right to penalize you for that, because you'd be repeating something you'd memorized rather than demonstrating any understanding. I remember my classmates bragging about "learning their times tables" and how they knew how to multiply all the way to 12 times 12! They were idiots, and so are you. But at least they were children.

10/30/2015 2:55:02 PM

i remember this shit pissing me off in elementary school because estimating is retarded if you know the exact answer.

10/30/2015 6:09:34 PM

Quote :

"And the teacher would be right to penalize you for that, because you'd be repeating something you'd memorized rather than demonstrating any understanding. I remember my classmates bragging about "learning their times tables" and how they knew how to multiply all the way to 12 times 12! They were idiots, and so are you. But at least they were children."

No, you demonstrate understanding in solving a word problem by sussing out the math involved and then solving it as you would another problem.

You also have managed to not read any of the other stuff I posted in this thread, or even in the preceding part of the post you quoted, but that's to be expected. You don't actually contribute to anything of value to a discussion in chit chat, all you do in is come in and try to show us all how witty and hard you are. That schtick was tired a decade ago, now that you're damn near 40 it's just sad.

10/30/2015 6:41:09 PM

I'm guessing the point is to understand X*Y as "X sets of Y" so "Y sets of X" would (rightfully) be incorrect. Same idea goes for the 2nd question.

I don't see what's so hard to grasp about that.

[Edited on October 30, 2015 at 7:30 PM. Reason : ^^needs more context. maybe they're learning about estimation and he was supposed to use it]

10/30/2015 7:30:00 PM

Kurtis636

when you are super angry

do you think you can suck bigger dicks

or just more dicks

show your work

11/2/2015 9:30:55 PM

^since you made a useless bump I'll restart the argument

Quote :

"I'm guessing the point is to understand X*Y as "X sets of Y" so "Y sets of X" would (rightfully) be incorrect."

Except that's wrong. X*Y doesn't mean X sets of Y. Fine to teach sets but unless you put more context in the problem then both answers should be correct.

11/2/2015 10:10:42 PM

I'm guessing the point is to continue to keep the United States as a follower in global education standards. Because memorizing times tables is such a terrible and useless thing...

11/2/2015 10:20:50 PM

i'm not advocating teaching rote memorization (at least not alone), sets is a great way to teach the concept of multiplication, just dont put in incorrect and confusing restrictions.

11/2/2015 10:30:21 PM

I think the confusing restrictions are clearly the problem with the examples in this thread. And rote memorization for certain things is not bad. It seems like teachers' examples in this thread are trying to teach children to run before they're ready to walk.

11/2/2015 10:33:44 PM

https://www.quora.com/Why-was-5-x-3-5+5+5-marked-as-wrong

11/3/2015 8:37:12 PM

neat repetition of 8 other posts in this thread

11/3/2015 9:42:47 PM

Quote :

"X*Y doesn't mean X sets of Y"

"times" is analogous to "of"

11/4/2015 8:25:43 PM

Nope

[Edited on November 4, 2015 at 9:25 PM. Reason : Are you a STEM grad or other ]

11/4/2015 9:20:57 PM

Quote :

"In word problems, the word of almost always means multiplication. So whenever you see the word of following a fraction, decimal, or percent, you can usually replace it with a times sign. When you think about it, of means multiplication even when you're not talking about fractions. For example, when you point to an item in a store and say, "I'll take three of those," in a sense you're saying, "I'll take that one multiplied by three."

elementary school

11/4/2015 10:43:28 PM

"of means multiplication" /= "multiplication means of"


if i have 5 stacks of 3 coins and want to know how many i have, writing 3x5 is 100% valid and certainly 3 sets of 5 does not apply.

11/4/2015 11:05:12 PM

Quote :

"And the teacher would be right to penalize you for that, because you'd be repeating something you'd memorized rather than demonstrating any understanding. I remember my classmates bragging about "learning their times tables" and how they knew how to multiply all the way to 12 times 12! They were idiots, and so are you. But at least they were children."

As a math teacher, I've had endless difficulties with high school students who haven't memorized enough. I have to walk students through Algebra and Calculus problems while they are still pausing to use their calculators for basic operations. Then, their brain power is diverted to something that ought to be trivial, adding complication to a problem that is already hard enough on its own. It's like trying to run plays with a varsity basketball team that still has to stop and think about how to put one foot in front of the other. Deep memorization gives students the freedom and excess RAM to tackle complicated problems later. I've yet to encounter a problem with students who memorized too much. It's like being too fluid or too coordinated on the court. Nobody ever said, "oh man, movement just comes too naturally for that guy. What a shame."

Even more importantly, a huge memory bank is what allows for deep thinking as an adult. You can't meditate on causes and interactions between events or ideas without having a large well of basic knowledge to use in the first place.

Over the course of an education, things that were memorized should be slowly deepened with the reasoning behind them. You move from the mechanics, facts, and rules of a thing, to the analysis of it, and then to expression about it. Attempting to do analysis without rigorous understanding of the mechanics and facts only asks for trouble. This applies in math, and just about every other subject.

I completely fail to understand how any of our educational issues come from too much memorization and not enough reasoning, as is commonly alleged. Simple quizzes on major things in history, government, math, science, or anything else quickly reveal that stuff was never memorized in the first place. We have far too little of it, not too much.

11/5/2015 1:11:39 PM

you're confused because you are trying to use performance on testing as your metric for knowledge when the problem may be that you need better tests

on the history test in your example, a student may know the context and circumstances of an event, they may know why it is important and what it caused, they could know how it relates to other events, but you seem more concerned that they memorize a few specific facts about it.

it's similar with math, memorization helps but you have to have the background understanding of what you are memorizing. I was taught math this "new" way so I can't relate to memorizing tables before understanding what they meant, but I can relate to my experience in differential equations memorizing patterns and not understanding what the fuck they meant. i could pass tests and do homework, but i had no idea what the math was actually for. when i needed differential equations in a circuits class i couldn't apply it at all unless the material was presented to me in a way that was familiar so that I could apply my pattern to it (it wasn't until vibrations when the concept was made clear and then I understood how easy that shit is and was mad I struggled for a semester memorizing patterns)

[Edited on November 5, 2015 at 2:19 PM. Reason : .]

11/5/2015 2:18:43 PM

I had that same experience with a lot of math classes, and in the engineering classes that used them. That's part of the purpose of the education. Only the very brightest and best students will have a full understanding of the class after taking just that class.

You and I learned how to push the numbers around the page in the right patterns. We learned the structures and mechanics of the language, but didn't really understand what we were doing. That made a class that focused on application (which required more full knowledge of why things were done) very difficult. The thing is, that stuff is already difficult anyway, but mastery of the patterns and mechanics lets you gather the theory. After the engineering class, you understood the earlier math much better.

Getting all of that done in one class, trying to make the math class do all of those jobs for most/all students, is just beyond most people's ability and brings more confusion than light. The next class always brings insight and understanding to the first.

This is part of what I mean when I say mechanics and grammar and such come first, with reasoning and such gradually revealed after an early focus on memorization. Most people will naturally learn this way anyway just to get by, as you and I did. The classes are fighting that natural progression when they try to introduce too much application and too much reasoning too soon, which lessens the mastery of the mechanics. Then you're just plain lost on both fronts.

The alternative to mastery of mechanics, followed by mastery of theory, is not mastery of both. The alternative is trying to do both, and getting neither.

There are also an infinite number of judgment calls required from the teacher, where he has to discern what is appropriate at each level to push understanding, while not making brains spin with too much depth.

[Edited on November 5, 2015 at 3:01 PM. Reason : j]

11/5/2015 2:51:59 PM

nah, that's wrong and dumb

11/5/2015 3:17:11 PM

I'll change the topic a bit to history. A contrast:

My work brings me into contact with students from all across the Triangle. I am not making it up that I can no longer assume that AP US History students know anything. Seriously, I cannot assume that they know when the Civil War took place, major generals, battles, or anything else. I can't assume they can identify the Axis powers, or the Louisiana Purchase, or Sputnik, the Cold War, or explain much of the Bill of Rights or the Declaration of Independence. However, I can guarantee that they've read multiple slave narratives, stuff about the personal lives of some people whose major accomplishments they don't understand, etc. They've read stories of the Jewish plight in Nazi Germany in great detail, but they don't know in what decade World War II happened. Teachers are so eager to get into the analysis, the background, and explain the reasons and means of history that students have no framework to put it in. That framework has to be composed of a long list of facts.

In contrast, I know a pretty bright, but not exceptional, student whose parents think a lot like I do. She is 10 years old. She can name every president in order, every war in order and some major battles and generals, the amendments to the Constitution and when they were passed, etc. She is more ready for AP US History than any of the students I've met. She's ready to learn the reasons, means, backstories, narratives, etc. They aren't. The parents have done the same thing with world history. You can name any century in the past, and she can tell you a few things that happened around the world at that time. She can describe all the major (and many minor) religions, even though the vocabulary in those descriptions is sometimes beyond her. All of that will come more over time, and she'll have a better understanding of world history by high school than most history majors.

11/5/2015 3:27:52 PM

wrong

11/5/2015 3:31:59 PM