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Just teach my kid the math

solipsys.co.uk

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Re: Just teach my kid the math

#21

Post by boblivion »

ColinWright wrote: post #11
jonsen wrote: post #8

Earlier quoted context omitted.

... makes perfect sense in the context of what the teachers are trying to teach ... What's the point with home work then? School takes the best part of a childs day, and when they don't make it through, the parents can finish with a tired child.

"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As someone not from the U.S. I wonder, what does "outdated" mean?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.

Re: Just teach my kid the math

#23

Post by mratzloff »

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; 173-57=43+73=110+6.

For multiplication, I do something similar: 6x57=300+42; 42x23=(42x20=800+40)+(42x3=120+6).

For division in my head, I use a kind of binary search to get a quick estimate and then refine it. 846/42=42x10? 42x20+6. 20r6. 6/42=1/7. 0.15x7>1, 0.14x7From my understanding, the Common Core approach to math is much closer to this approach I developed intuitively than the traditional methods. I'm sure many others developed similar approaches. If I want an answer accurate to more than two decimal places, or if the math gets too complicated to keep in my head, I just use a calculator.

Re: Just teach my kid the math

#24

Post by TheAdamAndChe »

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…

This is why I'm not opposed to the Common Core approach. It seems that they really emphasize math conceptualization and chunking instead of a formulaic process list that was used when I was a kid. Given the poor math scores in the US compared to other advanced countries, I really hope that this helps more younger people understand math.

Re: Just teach my kid the math

#25

Post by throwawaybbqed »

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.

I wanted to echo the parent poster. I'm in my 30s and math made no sense as a kid - precisely because the problems were all artificial and uninteresting. I had to fight major math phobia in undergrad. For me personally, the most interesting application of math was figuring out orbits/positions of stars, etc. I have a 2 year old so if you have another favorite example like this, I'd love to hear about it.

Re: Just teach my kid the math

#26

Post by watwut »

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.

You can teach multiplication as "here memorize that" or as "here is set of trics how to derive result" or even entirely diffreently.

Likewise with addition. You can mostly memorize that or you can tech them how to simplifie calculations. Thing like "17+5" is actually "17+3+2" which is easier to calculate.

Re: Just teach my kid the math

#27

Post by noir_lord »

throwawaybbqed wrote: post #25
boblivion wrote: post #21

Earlier quoted context omitted.

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.

I wanted to echo the parent poster. I'm in my 30s and math made no sense as a kid - precisely because the problems were all artificial and uninteresting. I had to fight major math phobia in undergrad. For me personally, the most interesting application of math was figuring out orbits/positions of stars, etc. I have a 2 year old so if you have another favorite example like this, I'd love to hear about it.

> the most interesting application of math was figuring out orbits/positions of stars.

For me math started to click when I started writing simple games for the spectrum, I realized quite quickly that what I needed was trigonometry and once I knew the name I could go to the library and get out books.

I was implementing a text based destroyer game (similar to mtrek/jtre though I didn't know those existed) and I had to implement handling bearings from the ship to the enemy ships, handle firing guns and missiles all that stuff, I made lots of horrible simplifications (shells experienced no air resistance so flew in perfect parabola's, the surface of the sea was a perfectly flat plane, no curvature (non-euclidean geometry would have been a step too far at 10-11) etc) but fundamentally it worked and was playable as a game, you could issue orders, fire shells (and later missiles though that made the game a lot more brutal and short) with bracketing and taking into time of flight - I was a strange child.

I got the original idea from a ZX81 kids book on game programming that implemented a simple side projection game where you set the elevation and velocity of your shot and aimed for the opponents ship, it was simple (couple of pages of code) and I wanted to do something a bit more realistic - as a side benefit I ended up reading up on naval warfare in quite a lot of depth, again a strange child.

Re: Just teach my kid the math

#28

Post by decasteve »

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…

I grew up being taught ‘borrow and carry’ methods. They are really methods of ‘apply the algorithm and success’. Common Core can be a better way of getting an intuitive sense of the numbers and quantities.

Some examples are over the top, like the 32-20 in the article. But one of the common criticisms my parents and grandparents used to level at people my age (when I was a teenager) was that we couldn’t run a cash register—-we didn’t know how to make change.

Kids won’t start out adding and subtracting as quickly. The ramp-up to learning may be a little slower but they’ll come out with a more intuitive sense of numbers.

All of this is just my opinion. I studied Math and have a couple of young kids going through these methods in school now.

Re: Just teach my kid the math

#29

Post by merraksh »

maximexx wrote: post #17

There is a reason why most people hate math. IMAO the current system of teaching math is ancient and above all deprecated. We should not punish our kids with it. I mean, what's the point of drilling stupid sums if you'll hardly ever need it in your life? I think it is totally stupid and irresponsible if anyone does calculations without a calculator for almost any application, not excluding: store checkout, health car…

I mean, what's the point of drilling stupid sums if you'll hardly ever need it in your life?

"Hardly ever"? So when checking the restaurant bill, the change at the grocery shop, the tax return, a bank investment proposal, the costs of building/renovating a house, the time left for a mortgage, do you always use a calculator?

Re: Just teach my kid the math

#30

Post by maximexx »

merraksh wrote: post #29
maximexx wrote: post #17

There is a reason why most people hate math. IMAO the current system of teaching math is ancient and above all deprecated. We should not punish our kids with it. I mean, what's the point of drilling stupid sums if you'll hardly ever need it in your life? I think it is totally stupid and irresponsible if anyone does calculations without a calculator for almost any application, not excluding: store checkout, health car…

I mean, what's the point of drilling stupid sums if you'll hardly ever need it in your life? "Hardly ever"? So when checking the restaurant bill, the change at the grocery shop, the tax return, a bank investment proposal, the costs of building/renovating a house, the time left for a mortgage, do you always use a calculator?

If I need to be sure? Yes!
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