(no subject)
Sep. 16th, 2022 09:48 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
cahnWELP my kids have been in school... three?... weeks and I have a rant!
I happened to ask A. about his math class today because I'd heard from a friend that A. had been placed in math class with her kid and our conversation made me curious about what math they were doing. A. told me that they were doing more complicated multiplication, and he further told me, in his calm but insistent and somewhat annoyed voice (that kid really does have superior emotional regulation) that his teacher had said he'd done a problem wrong and that he'd really done it right.
So I asked him to write it out for me. This is what he wrote:
(99*497) + (1*497) = __ *497 =
He further explained that the right side of the first equality was his explanation of how to do the problem, not what his teacher said. (He knew that in the blank space went 99 + 1 = 100, and then he could do the problem.) He said his teacher said that was wrong because there were parentheses, so he should do the multiplication of 99 and 497 because that was inside the parentheses. ("But it works!" he said about his method.)
(I think maybe she was trying to see whether he could multiply 99 by 497 -- which I don't think he knows how to do -- but then why not just give him that problem?)
Now, my children are famously unreliable narrators in the sense of being very good at leaving out context (this is the same child who said that his teacher takes balls from him, and we later learned that it was a game that his teacher was playing with all the kids during recess that involved them grabbing balls away from each other) so I should keep my mind open that it might be a misinterpretation or that additional context might make it okay. But... I really rather don't think there's additional context here that makes it okay. I mean, I think the additional context is that (I know from school gossip) his math teacher wasn't originally hired as a math teacher and got pulled into the job at the last minute, because you know, staffing.
We of course told him he had done it correctly and cleverly, and I am additionally pretty happy that he understood he had done it right even though the teacher had told him it was wrong. But ARGH. If I didn't have to work full-time right now (I have to work full-time right now) I would SO be spending some time teaching in our school, because they SO need help with lower-grade math. (Upper-grade math at this school has a lovely awesome teacher. Lower-grade math has been foxed by lack of good math staffing for YEARS. Fortunately for E, the lower-grade math problem happened literally the year after she went to upper-grade math.)
I happened to ask A. about his math class today because I'd heard from a friend that A. had been placed in math class with her kid and our conversation made me curious about what math they were doing. A. told me that they were doing more complicated multiplication, and he further told me, in his calm but insistent and somewhat annoyed voice (that kid really does have superior emotional regulation) that his teacher had said he'd done a problem wrong and that he'd really done it right.
So I asked him to write it out for me. This is what he wrote:
(99*497) + (1*497) = __ *497 =
He further explained that the right side of the first equality was his explanation of how to do the problem, not what his teacher said. (He knew that in the blank space went 99 + 1 = 100, and then he could do the problem.) He said his teacher said that was wrong because there were parentheses, so he should do the multiplication of 99 and 497 because that was inside the parentheses. ("But it works!" he said about his method.)
(I think maybe she was trying to see whether he could multiply 99 by 497 -- which I don't think he knows how to do -- but then why not just give him that problem?)
Now, my children are famously unreliable narrators in the sense of being very good at leaving out context (this is the same child who said that his teacher takes balls from him, and we later learned that it was a game that his teacher was playing with all the kids during recess that involved them grabbing balls away from each other) so I should keep my mind open that it might be a misinterpretation or that additional context might make it okay. But... I really rather don't think there's additional context here that makes it okay. I mean, I think the additional context is that (I know from school gossip) his math teacher wasn't originally hired as a math teacher and got pulled into the job at the last minute, because you know, staffing.
We of course told him he had done it correctly and cleverly, and I am additionally pretty happy that he understood he had done it right even though the teacher had told him it was wrong. But ARGH. If I didn't have to work full-time right now (I have to work full-time right now) I would SO be spending some time teaching in our school, because they SO need help with lower-grade math. (Upper-grade math at this school has a lovely awesome teacher. Lower-grade math has been foxed by lack of good math staffing for YEARS. Fortunately for E, the lower-grade math problem happened literally the year after she went to upper-grade math.)
no subject
Date: 2022-09-22 04:32 am (UTC)I mean... possibly because I personally learned order of operations relatively late (if I remember correctly), I use parentheses in a somewhat slapdash way -- I'll mostly use them where order of operations is unclear, but I'll occasionally use them in situations where they're redundant without caring too much. I mean, I wouldn't do that if I were writing a formal document! And, huh, I just realized that I'm more likely to use it for something like (3x3) + 2 than I am for 3.3 + 2 (where it seems more wrong) or 3z + 2, which obviously would be very weird to use parentheses for, lol. So it clearly has something to do with when I learned it!
no subject
Date: 2022-09-22 06:53 pm (UTC)I'll mostly use them where order of operations is unclear
Now I'm just nitpicking your comment, for which I do apologize! : ) But in which situations would you say that the order of operations is unclear? The only examples I can come up with of expressions which are unclear without parentheses are expressions with operations which are not associative, such as the expressions x/y/z and x^y^z, which genuinely are not defined unless you use parentheses. But that is not about the order of operations, which regulates priority among different operations. In expressions where you're mixing addition, subtraction, multiplication, division, the very point of having an order of operations is to make sure that the expression is always well-defined.
no subject
Date: 2022-09-22 07:29 pm (UTC)(Also, when I said 3.3 above, I meant 3 \dot 3, not the number "three and three tenths," which also in my brain made sense in context but uh, yeah.)
no subject
Date: 2022-09-22 08:50 pm (UTC)