P2 Math - General Discussion

[jesschan]

jiyou2003:

Yesterday DS mention that the silencer reading on every Tuesday is on Maths. May I know what kind of books is that? Any recommendation?

Many thanks in advance.

There are some simple books on Maths in the public libraries - they cover topics like counting, telling the time, money, shapes etc...in the non-fiction section.

[jiyou2003]

jesschan:

There are some simple books on Maths in the public libraries - they cover topics like counting, telling the time, money, shapes etc...in the non-fiction section.

Thanks this help, will drop by libraries over the weekend.

[corneyAmber]

http://i724.photobucket.com/albums/ww246/ks2me/P2MathTensOnes.jpg\">


Which would you choose?
1. 20
2. 29
3. 30
4. 210

Is this question considered tricky or ambiguous??? :?

[Way2GO]

Where did u get this question from?

From adult's viewpoint, it may look tricky.
(We see things or tend to read things dat may not be there?)

I asked my DS2.
His replied the answer is 210 and dat it is clear cut :roll:

[corneyAmber]

This is from St Hilda’s SA1 2009.


The model answer is 30.
My dd’s answer is also 210.

If the model answer is wrong, then no ambiguity.

Anyone from St Hilda’s P3 can confirm if the model answer is wrong?

I have 2 concerns though:
1. The quality of model answers from these papers.
2. Ambiguous question versus tricky question, sometimes adults mixed them up.

[Blobbi]

Here is a parallel case:


My son is completely bochap (read daydreaming) in class. Just before the March tests, he brought home some homework, each question with a picture that looked something like this:

ooo yyyy


With this, he was supposed to come out with two number statements.

Our friend wrote:

3 + 4 = 7

4 - 3 = 1

I didn't know what was going on - he never brought home his text book, so we had no reference :roll:. There was no other instruction on the homework sheet so it sure looked ok to me. Turned out the second statement should be 7 - 4 = 3 (or 7 - 3 = 4) to be a \"number bond\". The teacher did teach the format in class, and the kids are meant to replicate this style during the assessment. Luckily, we caught the format error (on his part).

So the school exam papers may show ambiguity. But if the kids have been taught the format beforehand, they will answer according to the prelearned format. My guess is, this is what's going with the St Hilda's paper in this case, because kids outside of the school are not exposed to the same context.

[KingRascal]

Showed to my P2 DS. He said the answer is 30 and he was not in doubt at all when I asked him why not 210.


He said under the "Ten" column the cubes are linked into one single bar. That stands for one-ten. Thus under this column it means 2 times of tens, which is 20. He went on to show me his math textbook, under Numbers up to 1000. This is how it is interpreted too.

[sunflower]

Hmm...I'm not sure but my guess is this, the boxes in the Ones column are all separated so each box is a 1, so 10 single and separated boxes equals 10 Ones.


In the Tens column, each small box (representing 1 unit) is joined together, so 10 of them together is 1 Ten, which again, is separated from the other Ten. So there are 2 Tens in the Tens column. So answer is 30.

Perhaps to make the question clearer, the lines separating the Ones boxes within the 1 Ten bar could be dotted lines.

[jedamum]

without looking at the answer, i guess 210; ds1 said 30.

the answer 30 is correct. those who has My Pals are Here textbook, pls refer to pg 10; the ‘working’ is there. so if the kids are taught like that in sch, they will probably get it correct.

[corneyAmber]

Gosh…gotta check textbook later. Thanks way2go, blobbi, king, sunflower n jedamum!!! I seem to learn sth new each day on conventions.


But why are we splitting hair on concepts with connected boxes and separated boxes convention?

My simple mind tells me the following based on concepts:

tens-----ones
5---------6

means:
50 + 6 = 56. If based on model ans, means half tens, =>5+6=11??