Active discussions

Meet the Other Phone. Flexible and made to last.

Meet the Other Phone.
Flexible and made to last.

Buy now

Please or to access all these features

Talk
AIBU?

Share your dilemmas and get honest opinions from other Mumsnetters.

Original poster

to point out to the teacher that a square is a rectangle?

216 replies

GooseyLoosey · 09/05/2011 15:11

Part of ds's homework was to draw on a grid 2 rectangles with a perimetre of 8cm. He drew a 3x1 oblong and a 2x2 square.

Aside from the fact these were the only possible shapes without using 1/2 squares, the teacher marked his homework as incorrect as a square was not a rectangle.

Ds (who is a perfectionist) read this and was not at all happy. He shouted "it is, I know it is, it is. Mummy, I'm right".

Would I be unreasonable to tell ds to ask the teacher why a square is not a rectangle? Or are we completely wrong and squares and rectangles are mutually exclusive?

(PS - I really don't expect teachers to always be right - God knows I am not but this teacher is the school's maths co-ordinator).

OP posts:
FreudianSlipOnACrown · 09/05/2011 18:14

"Surely the wonder and interest bit is what keeps most teachers going?"

That's what I'd hope. But it doesn't happen at all for my DSDs, both at primary and secondary. If they ask something different they get shushed because it's not in the SATs paper curriculum. Angry they are losing interest now and I don't blame them because there is no bloody point in asking. Double whammy for them because their mum tells them to be quiet as well. So it's only if they ask me or DH a question that they get any sort of answer.

heliumballoons · 09/05/2011 18:18

Squares are rectangles. Teacher is wrong, my friend a primary teacher says they are, my dad a maths professor says they are and me whos doing a teaching degree with maths as a subject says they are.

That was even without checking. Grin

Sorry not read past page 1, but I would go and see the teacher and point it out. Your DS should get extra credit for knowing this!!

confuddledDOTcom · 09/05/2011 19:02

According to wiki a rectangle is "any quadrilateral with four right angles. The term "oblong" is occasionally used to refer to a non-square rectangle."

bittersweetvictory · 09/05/2011 19:07

A rectangle is a square when both pairs of opposite sides are the same length. This means that a square is a specialized case of the rectangle and is indeed a rectangle.
Copied and pasted from math warehouse because to be honest i didnt have a clue so your DS is right and the teacher should know this.

penguin73 · 09/05/2011 19:13

A square is a rectangle but this tends not to be taught at KS2 to avoid confusion, otherwise lots of pupils think that all rectangles are squares which is clearly not the case.

Liliana1 · 09/05/2011 19:20

As a Primary teacher I know I am not always right (and am more than happy to tell the children I don't know the answer or have made a mistake, but we can find out about it together), however, yes I do know a square is a rectangle and both are quadrilaterals.

I love it when the children find out something I didn't know or find a solution I wasn't expecting. The best lessons can come from questions or ideas the children come up with and we can explore and discuss them. I would get your DS to tell the teacher what he found out - esp as he himself went and did the research, he should be praised for being so conscientious.

littlebrownmouse · 09/05/2011 19:20

A square is a 'special rectangle' it has all the properties of a rectangle - four right angles, opposite sides parallel and the same length. That's it, that's the properties of a rectangle. They're also the properties of a square. Teacher is wrong, pupil right.

littlebrownmouse · 09/05/2011 19:22

Penguin- I teach it at KS2 and so do all my colleagues. Don't think our pupils are confused...

Ilythia · 09/05/2011 19:27

I teach secondary and was all ready to teach pupils how squares are rectangles, but they already knew from KS2, so the teacher is wrong not to teach it imo.

pointydog · 09/05/2011 19:31

This would irritate me too. But then I would come over like a bit of a twerp if I corrected the teacher.

However, because of the square=rectangle issue and also the issue about 3x1 being different to 1x3, the desire to write a correction in the homework jotter would override my desire not to come across as a twerp on this occasion.

pointydog · 09/05/2011 19:32

Yes, certainly with yr 6 I say that a square is a rectangle when doing 2D shape. It's an interesting fact.

cazzybabs · 09/05/2011 19:35

All squares are rectangles not all rectangles are squares

BTW maths co-ordinator is not necessarily any better at numeracy than any other teacher

missmyoldname · 09/05/2011 19:45

I am crap at Maths and even I remember from school:

All squares are rectangles but not all rectangles are squares.

Hulababy · 09/05/2011 19:52

Just asked 9y DD (Y4) who is not a maths whizz in any form, just your average maths student. She also knew that a square is a form of rectangleand that a rectangle is a type of parrellogram.

Original poster
GooseyLoosey · 09/05/2011 20:06

We're right, we're right. Hooray.

I have written on his homework book that ds had looked it up and informs me that a rectangle is a shape with 4 right angles and parallel sides of equal length. A square is a subset of a rectangle.

I have never done this before and feel a bit of a pushy parent but I'll get over it!

OP posts:
confuddledDOTcom · 09/05/2011 20:50

Just finished reading the thread (had my dinner in the middle) and it has reminded me of conversation with my Child Development teacher. We had a question sheet for homework and I got one question wrong. I challenged her because I knew I was in the right.

How many people in the average family?

When I challenged her she realised that I was right and she had been wrongly marking every student for however many years right! She had wrongly marked my whole class right. She told me that she couldn't change the whole classes mark but the next class would be marked correctly.

Just had a story from our friend who said at uni his teacher wrote a long maths equation on the board that the class had to copy. He was the only one able to do the mental arithmetic to realise there was a mistake as the tutor was writing. As the tutor was correcting his mistake other students started calling out errors. The tutor had copied it from his folder and it was stuff he had been copying from for years.

InPraiseOfBacchus · 09/05/2011 21:25

A square is a REGULAR rectangle. Like an equilateral triangle is a REGULAR triangle.

DontCallMePeanut · 09/05/2011 21:29

A square is a rectangle - confirmed by friend doing a BSc in Mathematics Grin

DontCallMePeanut · 09/05/2011 21:31

Said friend has also asked that you tell DS well done for getting it right Grin

twoiscrackingup · 09/05/2011 22:05

This reply has been deleted

Message withdrawn at poster's request.

Loshad · 09/05/2011 22:23

good on your ds
many years ago when my ds1 was in y3 he brought some maths homework home, and one of the questions was incorrect.
Ds went to to school the following morning with a note from me mentioning the fact that the sum was incorrect so he hadn't done that one Blush
not one child in the class had done it - no surprises there
however they all recieved a merit for trying, where ds1 did not Hmm
story still in circulation by some of the other mums - some 9 years later Grin

IThinkTooMuch · 09/05/2011 22:28

This reply has been deleted

Message withdrawn at poster's request.

FreudianSlipOnACrown · 09/05/2011 22:40

"otherwise lots of pupils think that all rectangles are squares"

Seriously?!?

My 3yo knows the difference between a (non-square!) rectangle and a square, surely most DCs would not suddenly get confused by that info in KS2?

FreudianSlipOnACrown · 09/05/2011 22:44

"BTW maths co-ordinator is not necessarily any better at numeracy than any other teacher"

That's depressing - how the heck does that happen? If I go into teaching (having a bit of a confidence crisis ATM...) I want to eventually be in a maths coordinator sort of role - raising maths standards - and you're saying there may be people in charge of maths across a whole school who are not good at it?

Really hope that is wrong... :(