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Just teach my kid the math

solipsys.co.uk

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Re: Just teach my kid the math

#101

Post by ColinWright »

sctb wrote: post #79
patja wrote: post #78

I thought Hacker News preferred original source material rather than reblogging. Or is the original source not preferred in this case for some reason, for example being hosted on Medium? Original source: https://medium.com/q-e-d/just-teach-my-kid-the-expletive-mat...

Thanks! We've updated the link from http://www.solipsys.co.uk/new/JustTeachMyChildTheMaths.html .

And just for completeness ... now reverted because there is a good reason for re-hosting the article - Medium is blocked in some countries, and the re-hosting is to make it more widely available.

Re: Just teach my kid the math

#102

Post by ColinWright »

maximexx wrote: post #100
dorchadas wrote: post #42

Earlier quoted context omitted.

You want us to teach them best practice? Then we need to teach them maths, without relying on calculators. I teach secondary maths (specifically Algebra II), and they can't understand what I'm supposed to be teaching them because they have no clue how numbers work. Why don't they know this, if they're 15/16? Because they were given calculators at too young of an age and know "just push the button". What you're arguin…

> What you're arguing is for a complete removal of teaching math, period. No. I suggest focussing on explaining concepts, not drilling sums. And explain them why in ancient times the teacher used to use a cheat sheet because drilling didn't work because science found out our minds are not wired for that. Besides, from over 7 billion people on Earth, how many need Algebra 2? Please try to be honest and give us here an…

> I suggest focussing on explaining concepts, not drilling sums.

The research I've seen suggests that having a bunch of stuff at your finger tips then makes it easier to have the concepts crystallise. Trying to start with just the concepts doesn't work.

So what's needed is both, significant practice to help embed the simple underlying facts, with extensive exploration of the links between the facts to help the concepts emerge, be identified, and then distilled.

To me, it seems that almost everyone goes full extreme: "Must do this", "Must do that", whereas, as in game theory, it seems obvious that a mixed strategy is likely the best option.

Re: Just teach my kid the math

#103

Post by omnius19 »

meuk wrote: post #32
mratzloff wrote: post #23

When calculating in my head or on paper, I value quick estimations moving to greater refinement. Common Core math seems somewhat similar to this. I never subtract, only add up from low to high. If the two numbers have the same number of differing digits, I move from most significant digit to least: 73-57=10+6. If they cross a round number threshold greater than 10s, I get to a convenient base first: 2018-1995=5+18; 1…

Well, it is super useful do be able to do exact arithmetic. For example, to not get scammed when you buy anything, or share a bill. I've seen American university students who don't know how to compute a percentage of a given amount - so I'm not very impressed by common core math to be honest. That being said, it's probably a cultural thing too. I noticed that in the USA (at least in California?) it is customary to ex…

The mathematics standards for Common Core were released in June 2010. So college freshmen this year would have been in 5th grade (seniors in 8th grade) at the earliest when introduced to Common Core style mathematics. Probably later, since schools needed time to adapt to the new curriculum and train teachers in the new methods. Seeing as how Common Core places a heavy emphasis on developing skills in grades 1-8, I don’t think that current college students are a good benchmark for the Common Core standards. Talk to some college students in 5-10 years to get a better idea of how things are progressing.

Re: Just teach my kid the math

#104

Post by zaroth »

OscarCunningham wrote: post #97
zaroth wrote: post #84

I’ve watched my daughter do her 3rd grade math homework both ways. She’s an ardent rule-follower at her age (and can’t quite understand why the boys in her class can’t stay out of trouble) and really enjoys doing her math homework. Watching her work on the extra credit math assignments and her get so exited when the multiplication problems extend into 8 digits is a lot of fun. Often she will do the problem the “new”…

The amount of time and space needed for her to do the problem on paper are irrelevant. The only important thing is that she's understanding.

It’s more the incredible amount of time spent drawing it out and ultimately often arriving at the wrong answer due to drawings becoming so overly complex.

Despite her spending tremendous care at trying to neatly diagram exactly as she was taught, the methods apparently do not scale well past 3 significant digits.

It becomes an exercise in frustration which can take up to 10 minutes trying to solve a multiplication problem which she knows how to do properly in the blink of an eye.

There’s lots of graphite going on the page, but I’m highly skeptical of any learning. Certainly any love of math quickly goes out the window during the process.

Re: Just teach my kid the math

#105

Post by zdfjkhiuj »

zaroth wrote: post #84

I’ve watched my daughter do her 3rd grade math homework both ways. She’s an ardent rule-follower at her age (and can’t quite understand why the boys in her class can’t stay out of trouble) and really enjoys doing her math homework. Watching her work on the extra credit math assignments and her get so exited when the multiplication problems extend into 8 digits is a lot of fun. Often she will do the problem the “new”…

The woman in your video is just plain wrong. She's as wrong as if she claimed the sky is green or 1 + 1 = 14.

The Common Core doesn't specify curriculum. Period. Anyone who cites a specific problem or worksheet as evidence the Common Core is bad doesn't know what they're talking about. It's just evidence of an incompetent teacher.

Re: Just teach my kid the math

#106

Post by bfung »

jonsen wrote: post #94

I just asked my stepdaughter "What is 33 minus 18?" "Because ... 18 plus 18 is 36 ..... it's 18 minus 3 ... 15!"

Isn't it suppose to be:

  18 to 20 is 2
  20 to 30 is 10
  30 to 33 is 3
  2 + 10 + 3 = 15
?

Also, how does she know it's 18, plus an additional 18? Why not 18 + 20? What happens if it's 33 minus 21? 21 + 21 is 42...

Just curious - but at least she's got her own system that works!

Re: Just teach my kid the math

#107

Post by threatofrain »

omnius19 wrote: post #103
meuk wrote: post #32

Earlier quoted context omitted.

Well, it is super useful do be able to do exact arithmetic. For example, to not get scammed when you buy anything, or share a bill. I've seen American university students who don't know how to compute a percentage of a given amount - so I'm not very impressed by common core math to be honest. That being said, it's probably a cultural thing too. I noticed that in the USA (at least in California?) it is customary to ex…

The mathematics standards for Common Core were released in June 2010. So college freshmen this year would have been in 5th grade (seniors in 8th grade) at the earliest when introduced to Common Core style mathematics. Probably later, since schools needed time to adapt to the new curriculum and train teachers in the new methods. Seeing as how Common Core places a heavy emphasis on developing skills in grades 1-8, I do…

Also I would say that early CA Common Core for math basically just pushes up the current curriculum up about half a year, a mild improvement; more importantly it's a cleaner spec for outcomes.

It doesn't really re-order the curriculum, it uses a few new terms, there's mildly more emphasis on word problems, and there's earlier introduction to linear sequences. It's just a few touch-ups here and there, presumably to prepare kids better for Algebra 1. The whole reform is a modest start.

Re: Just teach my kid the math

#108

Post by bzbarsky »

boblivion wrote: post #21
ColinWright wrote: post #11

Earlier quoted context omitted.

"Homework" is supposed to be practising skills they have already learned so they can make it more fluent, and have to concentrate on it less when they come to the next thing to learn. Learning things is done with the teacher there to help anticipate, identify, and correct misconceptions. If you want the parent to help with the homework, the parent will have to know the material they want to help with. In maths, that'…

As someone not from the U.S. I wonder, what does "outdated" mean? Can you give a simple example - e.g. comparison - what would be "math back then" and "math nowadays". Because to me math was always just math especially if it comes to numbers.

Here's a simple example: Is sqrt(2)/2 or 1/sqrt(2) in "simplest form"?

The answer depends on whether you have a calculator handy. Because computing sqrt(2)/2 from a square root table and the long division algorithm is a lot easier than doing 1/sqrt(2). But on a calculator, 1/sqrt(2) is just as easy and it's simpler to write.

But at least as of the last 90s we were definitely teaching kids to put their radicals in rational-denominator form for basically "magic" reasons: the students had no idea why, and I suspect neither did most of the teachers.

Re: Just teach my kid the math

#109

Post by b1daly »

dragonwriter wrote: post #81
TheOtherHobbes wrote: post #12

Earlier quoted context omitted.

And techers are trying to teach how to make change? I understand “anchoring to fives and tens” but I don’t understand why anyone thinks it’s a good way to do anything except confuse kids. Does independent research prove these approaches increase numeracy?

> I understand “anchoring to fives and tens” but I don’t understand why anyone thinks it’s a good way to do anything except confuse kids. I found it a huge boost to my ability to do computations without paper or other tools when I learned it in elementary school; I think it's valuable, but I'm not certain that the manner in which it is often being taught now is helpful (which, AFAICT, is not so much a matter of the C…

I think the problem with how these new concepts are presented, is that they are taking these ad hoc methods of doing arithmetic and trying to turn them into algorithms. My guess is that this is driven by the need children have to know how to get the “the right answer.”

The traditional algorithms aren’t very intuitive, but they work. Trying to make an algorithm out of the various ways you can break up a problem, ad hoc, seems bananas.

Re: Just teach my kid the math

#110

Post by mocopoco »

This is like the things you develop yourself as a child although broken down and over simplified.

Maybe this should just be for the less intelligent children who do not have the skills to learn their own more efficient method.

I can see this wasting too much of an able pupils time.

Do you have streaming in America where you filter off children by ability like in Europe?, If so then maybe this is good for the lower streams to gain them insight into what more able pupils do anyway. (Though maybe not so convoluted).

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