Image credit: National Review

by Dick Hall-Sizemore

I have a dilemma. I can’t decide if I am just like most old farts who think “the way I used to do it” is the right way and the modern way is all screwed up, or if I am just out of touch with the modern way.

Here is the situation. As I have mentioned before, I volunteer in the local elementary school. I meet with a group of fifth-graders twice a week for about 25 minutes to help them with math. Most of the students in the group last fall simply did not know the multiplication tables well.  Therefore, I decided to drill them on those tables.

After their mid-year assessment, I got a different group of students. Almost all of these students know the multiplication tables. I realized I need to give them something more challenging. I asked a couple of students to show me how they would go about multiplying a double-digit number and a single digit, such as 14 x 7. One boy did the calculation in his head. The other student wrote it out.

The approach goes like this: multiply 7 times the number in the “ones” column—28. Multiply 7 times the number in the “tens” column—70. Add the two: 98.  This is done with a matrix of boxes into which the 28 is placed in one box, and 70 in the other and the two sums are then added. The “old” way of putting 8 in the “ones” column and “carrying” the 2 to the “tens” column is totally foreign to these students.

I understand the theory behind this current approach. It is an attempt to get students to see better what is happening in the calculation. But what if both numbers to be multiplied are double-digit or there is one three-digit and one double-digit number? The number of boxes being used could get awfully messy.

I asked the school coordinator of the “math club” these questions. Her response was that the goal was to get students to the point where they understood the “carrying” concept. Many students get to that stage, but others didn’t. And when I asked about multiplying more than two-digit numbers, she told me that, when they got to that stage in middle school, they were allowed to use calculators. I pressed a little bit more and learned that the SOL tests are constructed so that a calculator pops up on the screen for any word math problem and for any problem involving multiplying more than single digit numbers.

I may be old fashioned, but it seems to me that we are producing generations of students, many of whom do not understand the principles behind the math. They will just know that, when they enter some numbers into a calculator, an answer is produced. They will not understand the mathematical principles used to produce that answer. Instead of being a convenient time-saver, the calculator has become a necessary mysterious black box that produces the answer needed. (And I am not talking about the electronics involved. As far as I am concerned, it is a mysterious black box in that respect!) I wonder if this is part of the reason that American students seem to lag behind students in other developed countries in math. Or am I just being one of those who say, “Back in my day, we had to walk to school through two feet of snow uphill both ways”?


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50 responses to “Doing the Math”

  1. Chip Gibson Avatar
    Chip Gibson

    You are correct, Sir. Modern way is screwed up. Multiplication Tables were once 3rd grade.

    1. vicnicholls Avatar
      vicnicholls

      Wait … this isn’t 3rd grade math? I am thinking we did this before then.

    2. how_it_works Avatar
      how_it_works

      The Trapper-Keeper folders had a multiplication table up to 12×12 printed inside. I made use of it. Neither teacher nor parents ever noticed it was there.

  2. Eric the half a troll Avatar
    Eric the half a troll

    Get out your log tables!

    1. Kathleen Smith Avatar
      Kathleen Smith

      Better yet, a slide rule.

    2. Kathleen Smith Avatar
      Kathleen Smith

      Better yet, a slide rule.

      1. John Harvie Avatar
        John Harvie

        Only good to 3 significant digits mostly

        1. As I recall, we put a man on the moon by doing calculations on slide rules.

    3. In judging science fairs, many of the high school students will cite their p-value that was calculated using Excel or Google Sheets. HOwever, when asked to explain what a P-value is, most of those same students will give the definition of a 95% confidence interval. I have always blamed this on their teachers using older concepts that were based on pencil and tables versus new concepts based upon spreadsheets/math programs.

  3. James Wyatt Whitehead Avatar
    James Wyatt Whitehead

    I’m with you Mr. Dick. The old school way of carrying numbers is better. The whole calculator business while taking the SOL test, I never understood that. I am so glad that “I”, the world’s worst math person, did at least memorize the multiplication tables by 4th grade. 5 years of working in an old fashioned country store with an antique cash register taught me to make change in my head and get it right. There is something to be said about tried and true ways.

  4. Fred Costello Avatar
    Fred Costello

    The problem is not with memorizing the multiplication table. The problem is not putting more money into the school system. So they say.

  5. Bubba1855 Avatar

    I’m retired…many of us have ‘math’ stories. About 20 years ago my wife asked me to help her niece with geometry. When the child arrived we started with ratios…1/2=4/x. First thing the kid did was get out her calculator and punch in numbers. Of course she got 8.
    I asked her to do another simple ratio without the calculator and she couldn’t do it. I asked her some simple multiplication questions. she couldn’t answer. I told her to make some 3×5 cards with multiplications and come back in a week. Her mother called me to say I was too hard on her and she would not be coming back.
    And that was 20 yrs ago. Second story…my daughter was having trouble with geometry. I was a road warrior at the time. I went to her high school and asked for a used copy of her geometry book. I would call her each night I was on the road and would go thru her homework over the phone. After about 2 weeks we were working on side angle side profs. She just couldn’t get it. At one point she answered the problem correctly. At that point she asked…’is that all it is?’. I said yes. BTW, she graduated from college with a BSc in Math. Bottom line…some kids need help…sometimes it’s just a little help but it makes all the difference in the world.

  6. walter smith Avatar
    walter smith

    Your former option was correct.
    I helped my bonus baby some years back with a mild word with algebra problem and solving it as taught was convoluted. I pointed out the way I learned.
    But in the dark ages, in 3rd grade, in a rural county, we learned the multiplication tables to 12X 12.
    The kids today can’t do simple math.

  7. James Kiser Avatar
    James Kiser

    I kids today did their math the new way in an Apollo 13 situation there would be no survivors.

  8. Kathleen Smith Avatar
    Kathleen Smith

    Dick, since I had to teach the new math, for some reason I still multiply that way. It is easy once you have done it enough, just like doing it the old way once you did it enough. Try a two digit by two digit.

  9. Will Vehrs Avatar

    The “box” multiplication method is bad enough, but then you go into division using the “Big 7” method. Numbers are strewn everywhere because students don’t know the tables and have to incrementally multiply.

  10. LesGabriel Avatar

    I went to a one-room country school until March of 3rd grade. (I was the only 3rd grader in the school) By that time I had finished the multiplication tables. I then moved to “town school” and had a couple of dozen classmates and they were just at the beginning of learning multiplication. My Dad, who left school in 1921 after finishing 8th grade, was able to work math problems in his head faster than his boss could on a calculator.

  11. LarrytheG Avatar

    As important as remembering “how” to multiply and other mechanical techniques… done “long” division lately or get the square root manually, is does the result make real world “sense”?

    Do you really have 97.31 cents in your checking or 973 or 9733?

    Does a car stop in 3 feet or 350 ft. Is your car getting 98 mpg or 12?

    So, use a combination of your own memory, mechanics, and calculator, or whatever else but keep track of the numbers with respect to whether they make any sense or not.

    Worked with a bunch of mathematicians for 30-some years and
    and asking “does that number make sense” was core part of
    conversations when trying to verify results from computers and modelling.

    You can get close quicker if you do a “ball park” real world calculation then do the more detailed to get to a more precise number, i.e. the “answer”.

    You earn $3000 a month. A year? 10 x 3000 is easy, then add 6000…

  12. Matt Adams Avatar

    Definitely Yeomen’s work you’re doing and should be applauded. I don’t really understand the need to modify how it was taught in yesteryear, I’ve always carried as you described.

    I can’t wait to hear how they do long division now.

    As for the doing in the head, that would be an automatic 0 points awarded on tests when I was taking them, it was always show your work.

    1. Dick Hall-Sizemore Avatar
      Dick Hall-Sizemore

      I asked the boy how he did it in his head and he told me. Because it wasn’t test, I was impressed and pleased that he could do it without having to write it out.

      1. Matt Adams Avatar

        That’s fantastic.

      2. Matt Adams Avatar

        That’s fantastic.

  13. Marty Chapman Avatar
    Marty Chapman

    Oh Dick clearly math is RACIST!

  14. LarrytheG Avatar

    so this is why “multiplication tables” and such is not the complete answer for knowing how to do math:

    https://uploads.disquscdn.com/images/17b1f01364b5a793718bbe6dce5835ebcd1a6505099a1ac31423fe311c60c86e.png

    People will say, “we don’t do that kind of math, we don’t need to”.

    But that math and much more is embedded in everyone’s everyday life and those equations built by humans and incorporated into computer programs and models that, in turn, are used by all of us everyday.

    How much of that do most folks need to know? How much of “math” is used directly by most folks in their everyday life?

    Ask yourself, what was the last calculation you did and why.

  15. Nancy Naive Avatar
    Nancy Naive

    Right with you. A friend in college who entered teaching gave his first test (1976). After grading and passing them back, he held up a pocket calculator and said, “buy one of these and have your doctor sew it to your arm.” Apparently, that’s what has happened.

    I suspect that the problem they are having is not multiplying but because they never learned to add. The issue of the “carry” in multiplication is from the additions.

    I certainly would not recommend that students take 435 x 523 and write it (400 + 30 +5) x (500 + 20 + 3) breakout the 9 resulting multiplications, perform each, then do each of the additions, yada, yada, yada, but you could. It’s clarifying to do so, but impractical. It’s the “long” approach.

    The “short” approach (what we learned) does the calculations with a stack of repetitive left shifts and adds. This is what we were all taught. It’s just cleaner on the paper.

    Then, pull out an abacus…

    Pocket calculators are to learning mathematics what X(Twitter) is to learning social skills.

    I wouldn’t give a 6-year old a social media account. Why give one a calculator? Make thatt 16-year olds.

    1. A would expect a 16 year old to do math using Excel or Google sheets. That way the answer can be audited. Does anyone really believe that students need to learn to do a linear regression with a pencil or pivot a simplex tableau by hand?

      1. Nancy Naive Avatar
        Nancy Naive

        Don’t know. Who’s “A”? And, in what grade are K-12=students learning how to multiply (and divide) also learning to do linear regression?

        1. If one goes to a high school science fair, the kids are doing linear regression using the functions built into Excel or Sheets. They are getting exposed to statistics in earlier grades so that their science experiments are more meaningful. However, those students are not taking an average or doing an ANOVA table by hand. Also, they are no longer learning degrees of freedom or stats tables because the software does all of the work on that.

          And if a high school students has multiple numbers to add, they do in on a spreadsheet just like someone would do at their job. Calculators are old thinking because one cannot review the inputs to see if they are keyed in correctly and one cannot audit the answer.

          1. Nancy Naive Avatar
            Nancy Naive

            Ah, so.

            Yep, kids are having a good time. When the daughter was in HS, I taught her how to use MatLab image tools for one of her science fair projects. But, when she was in middle school, I pulled my CRC off the shelf one night and after a fruitless 15 minutes, she grabbed her trusty TI and left me alone.

          2. Nancy Naive Avatar
            Nancy Naive

            Ah, so.

            Yep, kids are having a good time. When the daughter was in HS, I taught her how to use MatLab image tools for one of her science fair projects. But, when she was in middle school, I pulled my CRC off the shelf one night and after a fruitless 15 minutes, she grabbed her trusty TI and left me alone.

          3. I had a job where we used Mathcad. At least one could audit other work and use the file to output subroutines and output data to make sure that the import work. I have only used matlab a little but it seems to be un-auditable for new, complex problems. It was the difference between a workbook based program versus a scripting based program.

          4. I had a job where we used Mathcad. At least one could audit other work and use the file to output subroutines and output data to make sure that the import work. I have only used matlab a little but it seems to be un-auditable for new, complex problems. It was the difference between a workbook based program versus a scripting based program.

  16. disqus_VYLI8FviCA Avatar
    disqus_VYLI8FviCA

    As my engineer dad told me years ago when I was in school, you can’t memorize math. You have to understand it, what is going on and why in order to master mathematics. Calculators can help with productivity after one understands the concepts. If they are the only way one can get the right answer…Houston, we have a problem.

    1. Dick Hall-Sizemore Avatar
      Dick Hall-Sizemore

      As I understand it, the current way of teaching multiplication of numbers with two digits is an attempt to show students what is going on. In my discussions, I have demonstrated what multiplication really is–finding out the total number of “things” in a defined number of groups each containing a defined number of thse “things”, i.e. if you have four tables that each have eight students around them, how may students do you have? I agree that students need to understand the principle, but after that, there is a certain amount of memorization involved.

  17. f/k/a_tmtfairfax Avatar
    f/k/a_tmtfairfax

    Memorizing multiplication tables. Night after night with my dad that did not stop until I could recite them correctly through the 12s. The saving grace was that the very same thing happened to my brothers.

    And then there were all those teachers who did not want just the answer to the problem. Show your work.

    Sometimes, pain is needed to progress.

  18. Innovation and experimentation are necessary to make progress. That applies to teaching as well. That said, not every innovation and experiment works as hoped. We should not fall in love with the innovation at the expense of what works.

    My sense is that in this particular case, the old, tried-and-true method of learning multiplication tables works best and students are losing something important by using a calculator for simple multiplications. So, yes, Dick, you are an old fart (like many of us who frequent the blog), but that doesn’t mean you’re wrong!

  19. I pressed a little bit more and learned that the SOL tests are constructed so that a calculator pops up on the screen for any word math problem and for any problem involving multiplying more than single digit numbers.

    And math SOL scores are still pathetically low.

  20. LarrytheG Avatar

    When we talk about SOL math scores, would anyone believe that it’s really great at some schools and terrible at others in the same schools district so that the overall SOL math score for 3rd grade is
    65 but check the individual schools scores:

    so is the problem every school in the same district? No.

    but there are enough of the low scoring schools to affect the
    over all SOL math score.

    What would be the SOL score if only done for the “Good” schools? in the 80’s and 90’s?

    Twin Hickory Elementary 94.78
    Echo Lake Elementary 94.67
    Tuckahoe Elementary 94.5
    Rivers Edge Elementary 94.31
    David A. Kaechele Elementary 91.86
    Jackson Davis Elementary 90.41
    Nuckols Farm Elementary 88.66
    Gayton Elementary 87.06
    Shady Grove Elementary 86.11
    Pemberton Elementary 85.71
    Colonial Trail Elementary 82.22
    Short Pump Elementary 79.27
    Glen Allen Elementary 79.05
    Springfield Park Elementary 76.24
    Maude Trevvett Elementary 72.63
    Three Chopt Elementary 71.43
    Harvie Elementary 70.65
    Greenwood Elementary 69.47
    Maybeury Elementary 68
    Crestview Elementary 66.67
    Pinchbeck Elementary 66.67
    Cashell Donahoe Elementary 64.94
    R.C. Longan Elementary 64.04
    Ruby F. Carver Elementary 63.86
    Chamberlayne Elementary 62.5
    Elizabeth Holladay Elementary 61.54
    Lakeside Elementary 60.34
    Sandston Elementary 53.33
    Arthur Ashe Jr. Elementary 51.32
    Dumbarton Elementary 50.91
    Skipwith Elementary 50.59
    Longdale Elementary 50
    Ridge Elementary 47.22
    Varina Elementary 46.67
    Seven Pines Elementary 45.45
    Charles M. Johnson Elementary 43.94
    Henry D. Ward Elementary 43.33
    Jacob L. Adams Elementary 43.18
    Montrose Elementary 41.67
    Glen Lea Elementary 31.82
    Harold Macon Ratcliffe Elementary 30.3
    Henrico Virtual Academy 28
    George F. Baker Elementary 26.47
    Fair Oaks Elementary 24.53
    Highland Springs Elementary 22.37
    Laburnum Elementary 14.29

  21. LarrytheG Avatar

    Part of the problem is a teacher problem. Not all math teachers are math teachers.

    1. And part of the problem is believing that everyone can learn calculus if they just had the right teacher. Also, another problem is the belief that everyone learns math the same way.

      1. LarrytheG Avatar

        3rd grade math though. But I totally agree that different folks learn different ways and apparently those
        that are economically disadvantaged are not taught in a way they learn so they actually drag down the
        overall SOL score for a given school district, in this case, Henrico. Ranges from 90’s all the way down to the 40’s.

        1. Several years ago, I read more educational blogs and websites. One of anecdotal stories was about teaching the students fractions, gett most of the students to be proficient, and then the students forgetting how to do fraction a few weeks later. The idea that those who are struggling with multiplication tables were never taught them before if laughable. The issue is with retention as much as teaching method.

          1. LarrytheG Avatar

            They do forget. Over the breaks and the summer, the ED one’s lose a lot. If they have parents who don’t see much
            use in math, it often follows with the kids. Past 3rd grade, the kids are much less interested in what is being taught
            if not relevant in their daily lives.

  22. Interesting questions Dick. But…

    How was your drilling students on multiplication tables teaching them anything about how to do math? That’s just rote memorization, it is not teaching anything about the mathematical principles involved. It’s very useful in everyday living, so I’m not picking on teaching multiplication tables, just that it’s a logical leap from there to choking on how slightly more complicated math is taught.

    Sanity checks when using a slide rule or just quickly estimating what a reasonable answer should look like are where I learned to use the ‘box’ method you describe. 7×14, lessee 10×7 is 70 (thank you rote memorization) plus a little less than half more. A very quick check, the answer should be around 100. When the calculator or spreadsheet comes up with 980 you know it’s time to look for an input error. When it comes up with 98, ‘ya go that’s reasonable and proceed.

    Don’t think I’d use the box method for calculating anything beyond about 2 digit numbers, as you note it gets complicated when the numbers get bigger. But the process remains useful for estimating the results of far larger calculations.

    1. Dick Hall-Sizemore Avatar
      Dick Hall-Sizemore

      I only have them for about 25 minutes twice a week. In addition, I don’t want to be teaching them to do things differently than their regular teacher tells them. Therefore, my function is to just help them on the basics. Another consideration is that I am not a math teacher; that is not my forte.

      1. Stanford math professor refers to memorizing math facts as foundational to all upper level mathematics. So does the 2008 National Math Advisory Report based scientific evidence.

        Lefty665 is still fighting the 90s Math Wars where NCTM in their 1989 Standards wanted kids as young as kindergarteners on calculators to “explore” problem-solving and discover the basics to modernize math (based on the 100 year old educational philosophy called constructivism – you see identical language in the New Math area as well as the VMPI presentations). The “rote memorization” slur’s constructivist roots are from the 1920s (really “modern,” just like the book the Great Gatsby).

        VA now requires automaticity (memorization of math facts), like 44 other states and the District of Columbia. Our new SOLs require it for 4 years, the most in the US (FL is 3 years, all other states that require it are 2). The SOLs require addition/subtraction in 1st and 2nd grades and multiplication/division in 3rd and 4th grades.

        VA had previously required it, but removed it as part of the 2016 SOLs along with the standard algorithm requirement. Just like Common Core (and 47 other states and DC), VA’s new SOLs also require the standard algorithm.

      2. Me neither. 3 thumbs up that you’re out there volunteering.

      3. Me neither. 3 thumbs up that you’re out there volunteering.

  23. Memorize multiplication tables so kids don’t have to use calculators.

    Okay. Memorize the meaning of every English word so they don’t need a dictionary.

    Physicians memorize every drug so they don’t need the Physicians’ Desk Reference.

    I recall decades ago there was a very popular sports show on DC radio station WMAL. Some doofus kept calling the show, asking the host some long-forgotten fact akin to “Who played 3rd base for two games for the Yankees in 1823?” to which the host replied something like “I don’t waste my time with something I can look up in about 30 seconds.” And that was before we had the Google machine.

    We put Glenn in orbit and brought him back using slide rules because that’s what we had. Should we go back to slide rules?

    I grew up in rural Mississippi where by granddaddy operated a cotton gin. My last summer to work in the gin, one morning I counted the vehicles haling the cotton to be ginned — 60% of it was in wagons drawn by mules. If we go back to horses and mules, we certainly could save a lot on fuel costs.

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