What am I missing here?

[Anonymous]

This was a question from the first unit math assessment done this year in my DC's 3rd grade class:

Estimate the difference:
854 minus 349 equals ?

A: 300
B: 400
X C: 500
D: 600 (CORRECT ANSWER)

[Anonymous]

854 rounds to 900

349 rounds to 300

900 - 300 = 600

[Anonymous]

854 rounds to 900, 349 rounds to 300. 900-300=600

[Anonymous]

The question said to estimate the difference. It is very close to 500, and nowhere near 600.

[Anonymous]

Estimation is taught in a rigid manner now - it’s a really stupid question

[Anonymous]

Anonymous wrote:854 rounds to 900

349 rounds to 300

900 - 300 = 600

It makes more sense to say 54-39 is negligible (estimation to beast hundred, so 15 rounds to zero) and 800-300=500

[Anonymous]

Anonymous wrote:

Anonymous wrote:854 rounds to 900

349 rounds to 300

900 - 300 = 600

It makes more sense to say 54-39 is negligible (estimation to beast hundred, so 15 rounds to zero) and 800-300=500

Pp- misread, minus 49, so even more negligible

[Anonymous]

OP here. So I asked my DC to explain to me how he did it after showing him this question in the report. He said he estimated 854 to 850, and 349 to 350, (i.e rounding both to nearest tens) and that's why he got 500. I told him that's great and that he is correct (and he should not worry about being marked wrong as 600 is a ridiculous estimate when 500 is one of the choices).

I don't think I have anymore faith left in how math is taught in our schools (never mind it's supposed to be an aap class). I was initially thinking in emailing and asking the teacher but realized it's probably not even their fault at all, as it's auto graded, and there is no point anyways as she couldn't/wouldn't do anything about it. The testing program appears to be called "Horizon Assessment System", so I don't think the teacher even had anything to do with the question. I'm just so glad he logically thought it out and didn't answer something stupid like 600.

[Anonymous]

Anonymous wrote:OP here. So I asked my DC to explain to me how he did it after showing him this question in the report. He said he estimated 854 to 850, and 349 to 350, (i.e rounding both to nearest tens) and that's why he got 500. I told him that's great and that he is correct (and he should not worry about being marked wrong as 600 is a ridiculous estimate when 500 is one of the choices).

I don't think I have anymore faith left in how math is taught in our schools (never mind it's supposed to be an aap class). I was initially thinking in emailing and asking the teacher but realized it's probably not even their fault at all, as it's auto graded, and there is no point anyways as she couldn't/wouldn't do anything about it. The testing program appears to be called "Horizon Assessment System", so I don't think the teacher even had anything to do with the question. I'm just so glad he logically thought it out and didn't answer something stupid like 600.

Telling him that makes you feel better but doesn't really help him.

He's in 3rd grade. What he learns now is important to him but won't last for a lifetime. Let his teacher teach him. If you teach him to ignore what his teacher teaches him, he will consistently answer incorrectly on all of his tests, which might make you feel better but won't help him

[Anonymous]

My kids hated estimation. They both could easily do that problem in their heads. It isn't hard to figure out at a glance it is 505. There is no point in estimating a problem like that. I would assume at least half if not way more of AAP students can also solve that mentally.

[Anonymous]

Anonymous wrote:

Anonymous wrote:OP here. So I asked my DC to explain to me how he did it after showing him this question in the report. He said he estimated 854 to 850, and 349 to 350, (i.e rounding both to nearest tens) and that's why he got 500. I told him that's great and that he is correct (and he should not worry about being marked wrong as 600 is a ridiculous estimate when 500 is one of the choices).

I don't think I have anymore faith left in how math is taught in our schools (never mind it's supposed to be an aap class). I was initially thinking in emailing and asking the teacher but realized it's probably not even their fault at all, as it's auto graded, and there is no point anyways as she couldn't/wouldn't do anything about it. The testing program appears to be called "Horizon Assessment System", so I don't think the teacher even had anything to do with the question. I'm just so glad he logically thought it out and didn't answer something stupid like 600.

Telling him that makes you feel better but doesn't really help him.

He's in 3rd grade. What he learns now is important to him but won't last for a lifetime. Let his teacher teach him. If you teach him to ignore what his teacher teaches him, he will consistently answer incorrectly on all of his tests, which might make you feel better but won't help him

No no, don't misunderstand, I did not tell him to go against his teacher. I've consistently told him that he always needs to listen and respect his teacher and answer even if he thinks it's boring (which he definitely does). Also I definitely don't think he answered incorrectly on purpose. He tries to do his best on tests, which is always a good thing. I don't think his teacher taught him that he always HAD to round to hundreds place (if so, then I'm glad it didn't register with him I told him that I'm glad he made a thoughtful choice vs relying on anything rote.

[Anonymous]

Anonymous wrote:OP here. So I asked my DC to explain to me how he did it after showing him this question in the report. He said he estimated 854 to 850, and 349 to 350, (i.e rounding both to nearest tens) and that's why he got 500. I told him that's great and that he is correct (and he should not worry about being marked wrong as 600 is a ridiculous estimate when 500 is one of the choices).

I don't think I have anymore faith left in how math is taught in our schools (never mind it's supposed to be an aap class). I was initially thinking in emailing and asking the teacher but realized it's probably not even their fault at all, as it's auto graded, and there is no point anyways as she couldn't/wouldn't do anything about it. The testing program appears to be called "Horizon Assessment System", so I don't think the teacher even had anything to do with the question. I'm just so glad he logically thought it out and didn't answer something stupid like 600.

I would talk to the teacher. Our kid is in high school, but when our child was in 3rd grade they used Horizon assessment. We would get back packets where our kid was correct (simple stuff) yet teacher graded incorrectly. This was on simple pre-Algebra stuff and not even estimation. Horizon was not good. I saved a few of them and had a meeting with the principal, who was embarrassed when I showed them the” graded” Horizon problems.

[Anonymous]

OP - are you sure the question didn't ask him to estimate to the nearest hundredth? Usually the questions I've seen tell you where to estimate to ones place, tenth place, etc.

[Anonymous]

Anonymous wrote:

Anonymous wrote:OP here. So I asked my DC to explain to me how he did it after showing him this question in the report. He said he estimated 854 to 850, and 349 to 350, (i.e rounding both to nearest tens) and that's why he got 500. I told him that's great and that he is correct (and he should not worry about being marked wrong as 600 is a ridiculous estimate when 500 is one of the choices).

I don't think I have anymore faith left in how math is taught in our schools (never mind it's supposed to be an aap class). I was initially thinking in emailing and asking the teacher but realized it's probably not even their fault at all, as it's auto graded, and there is no point anyways as she couldn't/wouldn't do anything about it. The testing program appears to be called "Horizon Assessment System", so I don't think the teacher even had anything to do with the question. I'm just so glad he logically thought it out and didn't answer something stupid like 600.

Telling him that makes you feel better but doesn't really help him.

He's in 3rd grade. What he learns now is important to him but won't last for a lifetime. Let his teacher teach him. If you teach him to ignore what his teacher teaches him, he will consistently answer incorrectly on all of his tests, which might make you feel better but won't help him

At some point you have to learn teachers are fallible and that you’re best off nodding and pretending they aren’t

[Anonymous]

Anonymous wrote:OP - are you sure the question didn't ask him to estimate to the nearest hundredth? Usually the questions I've seen tell you where to estimate to ones place, tenth place, etc.

Not OP. Yeah it looks like the question may have been to estimate to the nearest hundred.