Hacker Newsnew | past | comments | ask | show | jobs | submitlogin

This seems so strange to me, this sharp distinction between algebra and non-algebra. I might have gone to school in the Soviet system so everything was backwards and such but we were introduced to https://en.wikipedia.org/wiki/Elementary_algebra very early and just did simple expression transformations, variable substitutions. That was a lot early than 8th grade. I even taught my 2nd grader a few of those.

I have observed the curriculum so far in US, at least up until the 2nd grade and it's a hot mess. Even for double digit addition problems they jump right into "cool tricks" and "mathematical thinking" while there are just really a few steps to memorize and, guess what, kids are great at memorizing stuff. Later on it's time to show a few short-cuts and kids even discover those themselves.

Now going back to algebra, I am firm believer that a simplified version of this has to be introduced much earlier. It's a bit like a spiral, do basic arithmetic, geometry, number line manipulation, simple word problems, next year do the same but more complicated, add some algebra in there and so on.

But I guess that's just too boring and teachers, and probably higher level authorities, decide that they need to do "something" so they start making changes just to they can slap something on their resume. Developers do that too some extent, "here let me rewrite all this..." we can certainly understand that, but doesn't mean it's a good thing.



I read somewhere, don't remember where, that when a business isn't going well, people start grasping at "process improvements" like it will bring about a huge transform in the way business is going. In reality it doesn't, but it's the sort of busy-work that makes people feel like they are being useful.

I think it's very similar in education. There are vast swaths of the education system that are doing absolutely terrible. Much of the problems are outside of school administrator's control (broken families, gangs, poverty, etc), so they reach for "process improvements" and hope that makes a difference.


Maybe. Or...

> [a study looked at] the relationship between eighth grade enrollment [in Algebra] and National Assessment of Educational Progress math exam scores at the state level. In short, they didn't find one... [In a different study], they found that early exposure was actually associated with a net decrease in average student math score exams within a given district.

Maybe we're looking at the wrong metrics. Obviously introducing the average kid, whose average abilities change much more slowly than "process improvements," would have a decrease in today's math exam.

Maybe there's something wrong with the exam! And not in the sense of what questions it asks, but more like, who the hell cares?

I know what the answer is, I'm not stupid. But eventually, we'll have to square away the multitudes sitting inside of parent's brains: that they want their kids to actually learn something, while simultaneously having the highest scores / grades / metrics possible. The two cannot be true and honest at the same time.

But the tension isn't learning versus evaluation. It's honest versus dishonest. Under the early algebra scheme, you get a more honest evaluation (students perform worse at harder, more realistic material) and more learning (they're not rehearsing stuff that's easy for them).

The real dynamic is that no one is going to enroll their kids in a school with low test scores.


Sounds a lot like The Curse of the New HQ [0].

0: https://www.businessinsider.com/poorly-timed-headquarters-20...


Haha, my dad advised me to sell stock in companies that embark on a massive headquarters project. It's not just a curse - management spends their effort designing the HQ rather than working on the business.


Curriculum, most especially through 6th grade, is driven very much what whatever fad catches hold in the education establishment. It changes every 2 - 3 years. It's really just a symptom that there is very little accountability for the people making these decisions. Put out a curriculum with poor results? Who's going to notice? If anyone does, who will have the power to do something about it?


This lack of feedback can be extrapolated to the entire government. It's a well defined problem: https://mises.org/library/economic-calculation-socialist-com...


Do you think that is only a problem in government? Fads are a fundamental part of human nature.

In tech, we have many examples: Agile, Ruby on Rails, React, RISC, OOP, microservices, and so on and so on. All have some real benefits, but also have or have had huge hype cycles.

You can make the same argument for most other industries (if not all of them). And then there are things like diets, religions, etc.


> Do you think that is only a problem in government?

Nope. But businesses fail when they succumb to fads, while government just raises taxes.


School boards and other elected officials get voted out. Not every time, but businesses that latch onto fads don't fail every time either, as anyone can see.


Read the post you're replying to. The problem is lack of accountability, not fads.


And I think it's extremely harmful to delay these concepts for children like we do in the US.

I wasn't particularly smart growing up, but my parents always kept me up to date with the math and science curriculum they had at their respective ages in their own country. At least up until the end of middle school, the difference was astounding and had a dramatic effect on my academic (and thus future) success.


I wasn't particularly smart growing up, either, and I failed to place into the middle-school algebra classes like most of my peers. Somehow clicked for me in high school, though, and I raced through the curriculum at an accelerated pace, finishing with Calculus my senior year. A few years after that I graduated from MIT with an aerospace engineering degree.

My grandfather never advanced beyond trigonometry in high school, but went on to become a moderately famous theoretical physicist.

So if we're looking at anecdotes, it's hard to form a clear conclusion. Today I teach high school mathematics and I see accelerated kids who fall to pieces their junior year, and also kids like me who arrive in the 9th grade knowing nothing, but somehow end up in an accelerated track by the time they graduate.


Yeah it's interesting that grade 9 or 10 is kind of the point where students can make a complete turnabout in scholastic achievement and enter the accelerated track and get to a good university, etc.

In my case I started getting serious in grade 10, entered accelerated track for grade 11 & 12. Unfortunately I sorta peaked in grade 11 and started coasting in grade 12. I probably shouldn't have gotten serious until grade 11.


> And I think it's extremely harmful to delay these concepts for children like we do in the US.

I wonder how many people grow up hating math, like I did in elementary school, because they just don't like how rote arithmetic is and how trite simple word problems are because they steer away from algebra. It wasn't until I got to Algebra that I really, really started to love math.


I was an algebra teacher and tutor for years. It isn't the subject matter. It's the contextualization into the student's life. How is this relevant? I once taught a girl who was a soccer nut how to use algebra to budget for an imaginary soccer team. Soon it wasn't just basic algebra. We created a whole spreadsheet to calculate the entire thing. Change a number and it cascaded down to the final budget. She was jazzed.

It is vital not just to teach to the curriculum, but to teach to the student.

And that's where a lot of modern education falls apart.

It's not just algebra though. History. English (from literature to grammar). We're just failing to connect.


Why are you advocating memorization? That just gets people to treat mathematics as a set of magical spells you have to receive from the holy scriptures and priests, and that problems just can't be solved without having received the appropriate spell from the masters. (It also encourages strange beliefs like that mathematics is a subjective human construction, like art and music.)

Conveying that there's a deeper conceptual "mathematical thinking" seems much more important than memorizing the algorithm for "completing the square" or whatever.


> Why are you advocating memorization?

Because it's something kids do really well and it's something to take advantage of when learning at that age. In other words, it's better to memorize the multiplication table then find insights into how it work later, and do proofs and make connections with calculating an area of a rectangle etc. A lot of the tricks and insights don't mean anything to the children if they didn't already do many examples the rote, repetitive way and in a lot of cases the "insights" are often a distraction as well. Those should come later. Even more interesting is when children see or discover these tricks or rules on their own, then they become really memorable to them.

I don't have many samples work with, but I have observed this over the years based on my own experience, my kids and my extended family members and I have noticed the same patterns.


Memorizing the multiplication table is a useless waste of time and I recognized as much when they tried to make me do it and I refused. Nobody needs to know 8x7 off the top of their head. What's really important is estimation techniques to tell if something passes a sanity check, like reducing things to powers of 10/etc and seeing if they're close to the result you got on a calculator, like how 123x456 should be close to 50000 (100x500)


> Memorizing the multiplication table is a useless waste of time and I recognized as much when they tried to make me do it and I refused. Nobody needs to know 8x7 off the top of their head. )

Me too! I thought I was so smart as a kid, realizing that stuff I didn't want to do was useless.

However, I was wrong. An over-dependence on calculators due to a lack of arithmetic fluency has sabotaged all my encounters with mathematics ever since. I had a hard time understanding and developing any kind of fluency because I was forced to push everything through a black box that also distracted me.

I now realize that memorized facts are the foundation for knowledge and advanced thinking. Dismissing memorization, especially of fundamental facts, is like choosing not to use RAM because you can always swap to disk.


This is exactly what I tell my kids right now as they learn the tables by rote: knowing the answers instantly by drawing from your subconscious makes it vastly easier to solve harder problems later on.

Making it competitive between the two of the kids helps too... after all, sports is “just” being better at getting the ball in the goal better than the other team, right?


Higher math isn't harder arithmetic, it's increasingly more abstract and sometimes doesn't even involve numbers. A student with their times tables down isn't going to do any better in a calculus course than one who relies on a calculator.


I don't believe you're correct. As my 2nd & 4th graders' teachers tell them, they need to learn a set of level-appropriate "math facts" ... but they're not forced to start by memorizing those facts (my son, for example, has a printed multiplication table up to 15x15 to reference while practicing decomposition of 3 & 4 digit multiplication problems). I truly appreciate the Common Core principle of focusing on teaching methods over facts, and -- at least in my children -- it is apparent that it sets them up for problem solving success IRL. YMMV. It's not a perfect curriculum and is still tailored to the lowest common denominator student, but I do think there's value there. And again, in a classroom with a strong teacher who can take time for differentiated instruction, there are ample opportunities for advanced students to go beyond or to practice their learned skills by helping their classmates.

That said, I think your statement is absolutely incorrect in the context of higher math (and experimental science). The more facts you know -- whether literal facts, axioms, proofs, applied example or theories -- the more facile problem solving will be. This holds true in all disciplines (and not just math & hard sciences, but also engineering, social sciences & business).


A student with their times tables down isn't going to do any better in a calculus course than one who relies on a calculator.

A linear algebra course, on the other hand, is going to make mincemeat out of any student who can't do basic arithmetic in their head at high speed. Gaussian elimination, matrix multiplication, determinants, diagonalization; all of these tasks are extremely arithmetic-intensive. If someone needs a calculator to multiply 8x6 then they are not going to be able to solve a linear system in 4 unknowns on an exam that disallows calculators (which is all math courses at my university, besides stats and act sci).


Such a math course is being taught wrong if passing a test relies on churning through a million arithmetic steps instead of demonstrating understanding. I did fine in my course. Had to use the technique of mentally placing objects around a familiar path to memorize a silly list of matrix properties though.


The computational part was only 60% of the exams. The rest was proofs. For most of us, we needed every mark we could get in the computations because the proofs were really hard.


> Higher math isn't harder arithmetic, it's increasingly more abstract and sometimes doesn't even involve numbers. A student with their times tables down isn't going to do any better in a calculus course than one who relies on a calculator.

IMHO, that's wrong in many cases. For instance: there's arithmetic in algebraic manipulations, and a lot of that is in the times-table memorization range. I definitely had to rely on my calculator in calculus class (and specifically swapped professors to one that would allow the use of one for that reason).

There's also the fact that neglecting memorization as a "waste of time" at the start of your math career sets up a bad precedent and bad habits that will continue throughout it, barring substantial corrective effort.

I, personally, only stopped having problems due to my deficit when I got to discrete math, which was the one math class I took that didn't involve numbers, like you said.


> Higher math isn't harder arithmetic

That's narrowing the argument I made, I said "harder problems", of which higher math is just one aspect.

Even sticking to just higher math; you're going straight from arithmetic to... calculus? What about algebra, trig, geometry; all much easier when your arithmetic chops are blazing?


Statistics, on the other hand...

(Which is what most people ought to be taking anyway instead of calculus.)


What about statistics exactly? Bayes' theorem etc are enlightening and the numbers never gave me a problem.


Except memorizing multiplied numbers is not foundational knowledge for any higher math, knowing what the concept means is. Learning this involves working through some examples but it doesn't mean you need to know an entire table. Not knowing 7x8 never held me back in higher math/math-relevant classes like Calculus I-III, Discrete Math, Linear Algebra, Physics I-II, Chemistry, Macroeconomics, Computer Science (anything from basic programming to language processing or algorithm proof), Music Theory. Had a fun and mostly easy time in all those. Once in a blue moon on a test I'd have to do a multiplication and count it out (8x5, add 5 8 times) because it was a product in a derivative or something and that class had an (unrealistic for the real world) no-calculator policy. In fact I'm pretty sure mathematicians are notorious for poor arithmetic.

Additionally to your point, I think forcing arithmetic memorization on students is harmful because it makes math seem boring and hard.


> Except memorizing multiplied numbers is not foundational knowledge for any higher math

But my point wasn't that it's foundation in general, category theory, set theory, etc are foundational, but that it's important to start from it. Just because something is foundational doesn't mean it's a good starting point.

> it doesn't mean you need to know an entire table.

Kids at an young age are usually very good at memorizing things and once they have memorized then they can build on that and learn new tricks, relationships, abstract and foundational principles.

> Not knowing 7x8 never held me back in higher math/math-relevant classes like Calculus I-III,

Neither did me either. Embarrassed to say, I had forgotten a lot of it. But I would have been struggling early on in the 4-9th grades if I didn't know how to add or multiply numbers then. I would have been wasting time on tests doing it the slow way, instead of thinking of more interesting problems.

So to summarized, yes, it is not foundational but it all depends on age, it's better to take advantage of what the brain already knows how to do well at that particular state in time.

> In fact I'm pretty sure mathematicians are notorious for poor arithmetic.

Could be but if they are poor they would be left behind in early grades and might never becomes the mathematicians they are. There is also a bit survivorship bias in the sense that if there mathematicians who are poor ar arithmetic, they'd stand out and become memorable, but those that are good are not noticeable because they are expected to be good with numbers.


Do the memorisation by spaced repetition and make it competitive, and it takes almost no time to learn them. Of course if the kids begrudge it, they’ll hate it and fail to work at it.


The opposite extreme is when a smart child cannot solve a math problem, because despite having interest and some cool insights, and making a few hopeful steps, they predictably fail at one of the "2 + 3 = ?" steps.

Also, smart kids who hate memorizing are often really bad at languages. Which are mostly memorization; there is no way to derive the language from the first principles. But I guess if one's first language is English, this is not a big problem.

I get it: memorizing stuff doesn't signal how smart you are. But at some moment, the lack of factual knowledge is going to overcome the advantage of being smart. You will start making logically correct conclusions from factually wrong premises, and you will be proud that you didn't fill your brain with garbage.


I agree. That’s why there I some truth to the stereotype of Chinese kids being better in Math.

Mandarin has 5 tones and having a keen ear to identify each tone and then recognizing it and memorizing it and matching sound to meaning is an enormous advantage.

Also...teaching music..to recognize diff sounds/tones..musical notes(Bach would do) also gives mandarain/language/math students an edge.


I had a hard time getting in the habit of learning French but I adapted to it when I had to. However, as I've mentioned in another comment, shoddy arithmetic in particular was never an issue for me in real math contexts.


How in the world are you supposed to estimate products of large numbers if you don't know the products of small ones?


You'll pick up on a few as you go along and that's all you need.


So, you'll memorize them.


A few that you need, on an ad-hoc basis, instead of front-loading a bunch of calculations you're probably never going to use.


Memorizing every combo of 2-9 x 2-9 is only 36 numbers. That doesn't seem like a big waste of time to me.

If you do common ones like 2, 3, 5, and squares, that already covers most of them and you only have 10 left to remember them all.


I sort of both agree and disagree with you.

Being able to do mental arithmetic for small numbers is actually a very useful life skill. Sure, everyone has a calculator in their pocket these days (despite what my maths teacher told me), but that overhead of having to pull your phone out does slow you down.

But I don't believe that rote learning your times tables up to 12 is the way to do it. Mental arithmetic should be incorporated into the curriculum in a more integrated way. The problem is that school systems love testing and grading people. And it's quick and easy to grade people on their times tables by giving them a speed test to see how many equations they can complete in 5 minutes. You can say that little Jimbo is doing his times tables at a third grade level because he knows his 2, 3, 5 and 10 times tables. It's a terrible method of testing student progress though, I managed to get all the way to high school and was in the top stream class and never learned my times tables.

The actual concept of multiplication tables is an important concept for children to learn though, as it does help solidify fundamental mathematical concepts.


I do mental math all the time. Nobody needs to memorize tons of math but it's laughable that you would take that to such an extreme that you can't do basic multiplication without a calculator.


Can you give the example of the last mental math calculation you did? I almost never do it and I still almost never did it even when I was in college taking higher math. Tip calculation is all I can think of.


I may chime in with another story. I‘m teaching operating systems at university and use these skills (for small numbers, and written multiplication/division for slightly larger ones) all the time. My general consensus after overseeing a few hundred students is that those that are unable to quickly do simple math in their head also struggle with the rest of the curriculum. Especially if they need a calculator for computing 57:2 everybody gets distracted and we have like 2 minutes idle time while everybody starts entering the equation. I’d rather spend my time teaching actual os stuff, it’s a shame enough that I have to teach how to decimal <-> binary <-> hexadecimal base conversion.


I work in big data/cloud stuff so I do estimates all the time to figure out what size resources I need/how long something will take. Less than 5 minutes ago I did mental math to see how long a job would take (I knew how long it would take for one read, and I had 2 days of reads over 3 data sources each with 8 data partitions => 48 reads each taking about 90 seconds => about 1.25 hours).

Tip is another thing. And I like to "min/max" grocery shopping so I typically do mental math when shopping to maximize things like grams of protein/$.


I do rough division all the time in my head, for instance figuring out how much each can of beer costs if a slab of 24 is $60. Or on the flip side, how much it's going to cost me to get a round of 4 beers at $8 each.

It's just a general life skill.


I can be claustrophobic..I don’t like being in a closed car..so when I am at traffic stops..I convert alphabets to numbers and numbers to alphabets of the license plates..and sometimes I add the numbers together to check if it’s a prime number. Calms me the fuck down.


in farming..construction..cooking..I use it all the time in my everyday life.


The example of approximating 123 x 456 with 100 x 500 tends to undermine your point a little. It's too simplistic and the answer isn't even within 10%.

120 x 500 gives a much better approximation, and just needs you to know 12 x 5 = 60. Better still would be 125 x 460, which is 1/8 x 46 x 100000. That's within 3% of the true answer, and all it takes is quickly dividing 46 by 8.

It's very helpful to be on good terms with numbers less than about 100, which is why the multiplication table is taught. It's useful for reverse calculations (like 46 / 8) as well as forward ones. Decimal equivalents (1/8 = 0.125) are worth learning as well.

The key to being able to quickly approximate things is to populate your mind with memorized values. They work as landmarks (so the 7x8 example, in conjunction with the decimal equivalent of 1/8, means that you know almost immediately that, e.g. 55 x 125 is close to 7000).


You may be a bit embarrassed when you get older and a medical practitioner gives you a cognition test. Start with 100 and repeatedly subtract seven, announcing the results.


I'm certain they have different tests for people who don't have such arithmetic down.


Actually, that's on a standard cognition test. Other questions include identify pictures of animals, "what date is today", "Remember these five words (and get asked them at the end of the test), an "a is to b as c is to" question, etc. The assumption is that people over 50 in the USA can do simple arithmetic, because they all went to elementary school. Sadly, that assumption may have to change.


Addendum: I highly recommend this reading material, A Mathematician's Lament: https://www.maa.org/external_archive/devlin/LockhartsLament....


Although I tend to mostly agree with your main argument, the example you presented ( memorizing multiplication tables ) is a bad one. My mind was blown when I found out how they teach multiplication to children in Japan. Link: ( Vedic method ) https://www.youtube.com/watch?v=z4X98Mnj0tc The superiority of the teaching method shows to be significant when compared to other teaching methods elsewhere and even remains noticeable when children encounter higher levels of math.


This is similar to the "Lattice Method" that they taught (still teach?) here in the US. I can't stand it. The students simply learn an algorithm, without developing a sense of place value and an intuition for "how numbers work." Sure, they can quickly multiply large numbers and it's a cool "party trick." But they aren't learning math. Might as well use an iPhone.


Fair point that memorizing an algorithm doesn't necessarily advance the student's intuition for how numbers work, but keep in mind that you're replying on a subthread about how learning a general algorithm is an improvement over memorizing multiplication tables.

Ideally, we teach children the intuition for mathematics. Just memorizing arithmetic algorithms isn't ideal, but it's surely better than memorizing finite arithmetic tables.


I don't think it is better to learn some shortcut algo at a young age. Memorizing your times tables up to say 10 * 10 or 12 * 12 is fundamental to understanding multiplication. Remember, the brain is not a turing machine, it's an associative memory machine. Facts are the foundation of knowledge.

First memorize the times tables. Then learn the long method. Then learn the shortcuts. IMO, of course.


I agree with you. To do multiplication by any non-parlor-trick method you have to be able to multiply single-digit numbers. If you don't memorize the table then every time you do larger numbers the process becomes that much more of a chore.

Now, that is not to say that you should forego understanding multiplication. But forcing student to memorize the basics (like forcing them to memorize verb forms) (1) makes their life easier later on and (2) gives them the chance to spot patterns themselves.


> The superiority of the teaching method shows to be significant when compared to other teaching methods elsewhere and even remains noticeable when children encounter higher levels of math.

I was mainly talking about addition and multiplication up to 10x10. Looking through all the tricks and hacks they teach the kids in an attempt to simplify ideas seems very wasteful as the brain at that age is so good at memorizing things. ut the schools don't seem to be taking advantage of that.

They think like adults in the sense of "oh let's introduce this abstract idea and prove it and derive the specific examples from it". Yes, a college kid or high school would do well there, but in earlier grades I haven't seen it work. It's a bit like learning a language. An adult might do well to start learning about grammar rules, tenses, cases etc, a kid might do better hearing a lot of example and deriving the rules on their own. Later they might find out that there are 8 tenses, 4 cases, predicates, adjectives etc.


Memorization is very important. You have to walk before you can run.

To perform well at algebra, you can't be stopping to punch numbers into a calculator. You can't be constantly making mistakes. The slowness and errors will make you stumble and lose your train of thought, preventing you from reaching any deeper conceptual "mathematical thinking".

Those old-fashioned methods for doing math are reliable and general. If you follow the rules, you get the answer.


That's what my typing teacher taught me about typing, that by not memorizing all the key+finger combinations I would never type (Owning a computer, I was self-taught and used all the wrong fingers). Twenty years and a law degree later, after authoring literally thousands of pages, I still cannot say which finger is supposed to hit the 'r' key. Somehow I muddled through. The point is that rather than memorize combinations of seemingly random numbers, the same knowledge will come naturally as students learn other aspects of math.


Seems to me that you just spent twenty years to slowly develop muscle memory, when you could have achieved the same results in a few weeks. (I did the same thing.)

> the same knowledge will come naturally as students learn other aspects of math

The key difference here is that being slow at typing for twenty years didn't discourage you from typing. Being slow at math can discourage kids from doing math, and the "twenty years of regular practice later" moment will never arrive.


I can't recall the commands to my text editor. I just look at my fingers to see which keys they hit.


Yes - When someone asks me what a particular key combination is in emacs or Eclipse, I put my fingers out like they're on a keyboard, think about doing the thing, and, look at what my fingers are doing.

To bring it back to the article: It's similar with a lot of things - you sort of need to memorize aspects of it to do it fluently. As part of calculus, you sort of need to know how to do polynomial factorization. Intuition is great and helpful, but you also need to be able to proceed methodically in order to produce or understand proofs. Scales on piano are boring, but you don't just tell kids to feel like they're Bach and they start playing Goldberg Variations. Why on earth we think the intuition is not only necessary but sufficient is unfathomable to me.


Simple. You use the r finger.


I recall research showing mathematics being one of the very few subjects where one can get better at through brute memorization. It gets you quite far in that field, as it reduces recall time for proofs etc, and then it becomes like muscle memory.

Practice/muscle memory in other fields, like the physical sciences, can not come from a page out of the book, since it requires interacting with nature in a multi-sensory way.


My impression is that mathematical thinking isn't really the goal of mathematics education until post-calculus University level. Before that it is mostly learning rules for doing symbol manipulation.

Although, this isn't entirely true, I remember doing proofs in Geometry class in Jr High School. So I was at least introduced to it, though we never really used it again.


Sorry that is pure BS. Memorization is a great technique to learn math of course it is not the way to do math. When you learn tables through rot learning you automatically get how they are being computed. At young age it is much easier to rot learn many things and understand the abstract concepts much later.

People who despise rot learning are either misunderstanding it or are simply lazy.


See Piaget's concrete operational stage [1] of human development: "Abstract, hypothetical thinking is not yet developed in the child, and children can only solve problems that apply to concrete events or objects."

In other words, you can only push the mathematical thinking as far as the developmental stage of the child allows you to. Memorization helps though.

My son is 6. He doesn't know the multiplication algorithm, but he does know that 2 x 2 = 4 or that 3 x 4 = 12. That's sufficient for him to do discoveries of his own. 3 x 4 = 3 x (2 x 2) ! Picture that!

[1] https://en.wikipedia.org/wiki/Piaget's_theory_of_cognitive_d...


"In mathematics you don't understand things. You just get used to them."

-John Von Neumann


I'm not seeing any advocacy of memorization? The only thing you might have to memorize, out of what parent listed, is the algorithms for doing written out arithmetic; and that too is in fact an exercise in mathematical thinking. After all, there's a reason we teach these algorithms, as opposed to just telling kids that they can punch numbers into a calculator.


Quote: "Even for double digit addition problems they jump right into 'cool tricks' and 'mathematical thinking' while there are just really a few steps to memorize and, guess what, kids are great at memorizing stuff."


And rdtsc is entirely right about that. The Common Core math curriculum has been taken by many self-described "math teachers" and "educators" as an opportunity to just not teach the effective algorithms for doing arithmetic, and expect students to just "discover the results by themselves" via some mixture of trial-and-error, random guessing, and the rare "trick" or perhaps tiny flash of genuine "mathematical thinking". That was an unmitigated disaster, of course. It's probably part of the reason why Algebra is now being seen as way too difficult for Junior High students, and something that only HS students could approach effectively.


Effective arithmetic algorithms are included in Common Core [1].

[1] http://www.corestandards.org/Math/Content/NBT/


From your link, knowledge of the standard algorithm for addition/subtraction is only requested by Grade 4, and for multiplication by Grade 5. So the Common Core standard is basically relying on a hidden assumption that students can effectively learn all the other stuff that's expected of them up to Grade 4 and 5, without truly being fluent in addition, subtraction or multiplication! (I'm aware that the standards call for "fluency" slightly earlier, but that's mere wishful thinking until you teach the standard algorithms, or some cosmetic variant thereof such as lattice multiplication.) That's what so bad about the way CC is being applied in elementary education.


Holding off algebra to high school predates common core by decades.


This debate comes up again and again, and any time one view is purported strongly over the other we just get education that is half-assed. This includes people with your point of view that deliberate attempts at committing propositions and procedures to memory should be avoided.

The issue is one of cognitive load. You can't get to mathematical thinking and appeal to both a higher-level "intuition" or "key idea" if you aren't fluent in the details. Else it becomes hand-waving that doesn't cash out to proof-ready reasoning. Likewise, you can't internalize the details if you don't have a principle which compresses them and lets you unpack them appropriately for the circumstance of the problem. This is fair, but first there has to be something to compress.

The question is, "How much detail can be advanced at this point in the student's growth?" If the key issue is to dispel the notion that mathematics is arcane, you should narrow down the scale of the problem so that you can quickly see how the details contribute to generalizations, and how a procedure can be taken from it. This achieves what you are looking for with less effort and less risk.

With that point of view illustrated with a simpler case, it can be developed or built upon with bigger cases. Bigger cases inevitably means more details to internalize. This protracts the phase where memorization would be appropriate. But the student, having seen how mathematics is developed in a simpler case, would understand that these details have a context that will be more adequately realized at a second or third pass of the material.

Eschewing the internalization of detail as you are purporting would encourage a sense that math is subjective, because the high-level impressions of mathematics would not have the memories of detail to back them up, allowing for more to be said, with less control.


Same. My grandmother taught me how to solve equations, and we'd do it for "fun" on the bus in Moscow; I was in, at most, fourth grade. And you know what, it was fun, and it wasn't hard.

Granted, she was also a programmer, and my grandfather was a mathematician, and both my parents were engineers - so maybe my baseline for fun and education was set differently.


Wow! Can you share, if you know, what kind of programming your grandmother took part in?


I'm a bad grandson, so I have no idea! I'll have to ask.


I doubt you're a bad grandson, but I'll share this story with you.

I was raised by my grandparents, and I had enormous respect for my grandfather, who was the most badass human being I've ever known, though you would never know it to see him. He was very quiet, he spoke little, always watching and listening.

But he grew up in the https://en.wikipedia.org/wiki/Great_Depression and fought in https://en.wikipedia.org/wiki/Guadalcanal_Campaign , with https://en.wikipedia.org/wiki/Merrill%27s_Marauders among others.

He was in his 50s when I was born and lived with them permanently when I was 5 years old. He and my grandmother were my parents.

They were always patient and kind, and always stoic about everything. One day while camping my grandpa was sitting next to a dart board, and one of the darts I threw went crazy wild; it hit and stuck deeply into his left calf. I just stood there with my mouth open while he puffed his pipe, staring at me. After a couple of moments, he calmly pulled it out, wiped the blood off of it, and carefully tossed it back to me, saying, "Careful where you throw those, boy."

I always had a lot of respect for them, though I didn't show it. In fact, by my actions, I took them for granted.

They both died of old age when I was in my 30s, even as I was just starting to truly appreciate them.

Now, many years later, I would give almost anything to be able to spend another day with them. There's so much I'd ask, so much to learn.

In summary: spend as much time as you can talking to your grandparents while you still have them, because once you're old enough to really appreciate their value, they might be gone.


My impression is that the schools are endlessly looking for a way for kids to learn without effort and teachers to teach without doing any work.

It's like giving a jogger a car. He arrives at his destination faster and easier, but didn't get any stronger.


Dragonbox produces an Algebra game for small children-- symbolic manipulation isn't that hard, you just have to be taught the rules: https://dragonbox.com/products/algebra-5


Some school districts in the bay area are doing better than San Francisco.

In the Los Gatos school district my daughter completed her first year of college level calculous and some second year calculous by the time she graduated from high school. This was better than my education as I only had access to pre calculus in my high school.

As an aside - giving kids math puzzles is a much better preparation for math than memorization. The only thing I had to memorize was the multiplication table, everything else I could derive. I could always derive a formula faster than memorizing it even at a young age. I went to school in the era of "new math" where we were introduced to functions and variables in 2nd grade.


I don't think anyone is suggesting that more advanced high school level math should be transformed into an exercise in memorization. They're talking about kids that are 7 or 8 years old memorizing their multiplication tables.


We might be saying the same thing since the only thing you need to memorize is the multiplication tables. ;-) How long can that possibly take?

My grandsons are between 3 and 8 - so they are in this age group. They are amazing at solving problems when it leads to something they want like winning a game against their brother. Puzzles are great for teaching math to this age group.


Spiral curriculum is actually a widely used concept in teaching...

https://www.teachwire.net/news/ever-increasing-circles-what-...


> ...so they start making changes just to they can slap something on their resume. Developers do that too some extent...

To some extent? Sometimes I feel like that's the only thing that developers do.


> kids are great at memorizing stuff

Some are good at it, some are not.

This curriculum is aimed at equalizing things for those who are not.


It's a relative comparison. Kids are far better at memorizing stuff and dealing with things that have been made "concrete" to them, compared to abstract thinking - because effective abstraction requires a sort of overall maturity of thinking that very few kids can be expected to develop at an early age! So it's better to just teach the memorization and concrete steps first, and focus on the more abstract stuff later on.


It would be good to find a way (an alternate path) that helps the kids who aren't great at memorizing. But don't do it in a way that makes things worse for the kids that are good at memorization. Don't "equalize" by making the best worse.


The key to memorization is repetition. Also, paying attention.

If I had to design a system that helps everyone with repetition, it would go like this:

- each concept must be explained and understood first (never progress to repetition unless you are sure the child groks it);

- afterwards, add the concept to your "spaced repetition" software (conveniently provided by the teaching institution);

- give kids some time at school when they can do the spaced repetition exercises (so it doesn't become an extra homework).

The first step avoids the kind of stupid memorization that people do when they don't have enough time, and that gives them problem (and even greater time pressure) in the future. This makes the entire thing more meaningful that current education.

The second step avoids the situations like "I felt pretty sure I understood it yesterday, but now I have no idea where to begin". This makes the entire thing more efficient.

> But don't do it in a way that makes things worse for the kids that are good at memorization.

Uhm, if you complete the spaced repetition exercise and there is still some time left, you can go play or read something. Or perhaps take a bonus lesson that is not a part of the standard curriculum.


Yes, but what did the Soviets know about math? Uh, Kolmogorov, Gel'fand, Dynkin, Shiryaev, Pontryagin, etc.????

My take is that by age 12 they should be doing calculus from one of the best college texts.


Kolmogorov had to go against a strong political pressure to convince the government to allow him to create a school for mathematically gifted kids.

Also, a large part of Soviet mathematical output came from people who were politically forbidden from getting an official scientific job (and then the Academy of Science was filled with people like Lysenko), and sometimes had to get a manual job. So they did math in their free time, corresponding with each other. Which, paradoxically, probably provided more freedom than they would get in an academic institution: no pressure to "publish or perish", freedom to spend years solving some obscure problem with no impressive intermediate results, true cooperation between the outcasts instead of fighting for a limited number of academic job.

A large part of Soviet mathematical progress was made in opposition to the regime. Or perhaps, to put it more mildly, the system was so hopeless that people didn't waste their time, and organized better mathematical education outside the system. Then they created things like the International Mathematical Olympiad (the first twenty years, it was an Eastern Bloc thing), various correspondence seminars, etc. But this all happened outside the official educational system.


My understanding of "strong political pressure" for the years of Kolmogorov in the USSR meant that ended up in a salt mine in Siberia and dead in a year or so. But apparently somehow Kolmogorov was smart enough to avoid that end.

Yup, suspicions confirmed, all around the world, no matter what, bureaucracies have a lot in common: If have something good and want to kill it off, then set up a bureaucracy to help it!!!!! That's partly a black joke; likely the US NSF and NIH and lots of private efforts in math, physical science, medical science do terrifically good things. And, no joke that the LHC is a big bureaucracy and found the Higgs Boson, a darned good thing.

Still there can be some truth to the joke. E.g., in the US I've seen some of what you said about publish or perish: While I never really wanted such an academic research career (I just wanted a JOB and to support a family and looked at my math Ph.D. as vocational education), eventually it dawned on me that actually in some fields the publication standards sufficient for publish or perish are low and that a good researcher should be able to toss out dozens of such papers, if only as side efforts, while otherwise doing the important stuff.

Bluntly when I was considering academic math research, the main obstacle, and it was SEVERE, was that I didn't quite yet have access to a computer that could run Knuth's TeX math word processing software. Bluntly the word processing for typing in the math research was MUCH more challenging than doing the math research!

There's another relevant rule: In social, political, bureaucratic, etc. systems, when want to do better, measure it, and, for that, create, design, implement, and setup measures.

Then the system responds, does well on the measures, just the measures -- games, hacks, manipulates, tricks, fools, takes advantage of weaknesses in the measures -- with harm to what was being measured! Partly another black joke but, still, with some sad truth.

With bad measures, the Soviets were not the only ones with the problem of "They pretend to pay us, and we pretend to work.".

Then we get reminded that democracy and free enterprise are the worst systems ever invented except for all the other systems that have ever been tried. Another black joke; sometimes democracy and free enterprise do really well. E.g., in a democracy, we can elect liars, crooks, incompetents, etc. but eventually the disaster becomes obvious to enough voters, and then we get some better candidates and an ELECTION to throw the rascals out -- been known to happen, sometimes slowly, but, still, happens.

I know next to nothing about the Soviet system, but from what little I know it looks like it was an astounding juxtaposition of just horrible suffering and lost opportunities, waste, e.g., on military efforts, lots of just horrible inefficiencies, yet at times some, maybe not enough, maybe with the movie remark "But do you know what it cost?", astoundingly good things -- Kolmogorov, Oistrakh in violin, Giles in piano, Garanca in voice (grew up in one of the Baltic states when they were part of the USSR), the Mariinsky Ballet, etc.

I'm trying to get my startup live on the Internet; there are some ways it could help civilization. Otherwise I can't solve all the problems. But democracy and free enterprise when they work well -- in the US from 1929 to 1942 they didn't work so well -- can be amazingly good things.




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: