Eek - need help with Y3 3D shapes Homework

[sydenhamhiller]

I may be over-thinking this...

1. We have to label 3D shapes with the correct 'name'...but looking at some shapes, I am not sure if we should give them the label of 'cuboid' or 'prism' (both there in box to choose from)?

One definition of a prism is that it is a solid object with 2 identical ends, and all flat sides - which sounds like a cuboid... Do I call the variously shaped toothpaste/ cereal boxes cuboids or prisms??

1. Does a cone have a vertex? (corner of 3D shape) On line, a helpful maths forum states stroppily: "Too many texts ask this question, which really shouldn't be asked."

I got an A for O level maths (pats own back), I foolishly thought I would be OK at this level of HW...

Any advice or help is gratefully received! :)

Cuboid = 3D rectangle
prism = extended triangle/hexagon (usually)

cone= circle with pointy top.

You really are overthinking it! if you do want to google, make sure you put primary maths in the search!

Sorry, but homework is for your child not you - surely they should know some of these answers!!??

A cuboid is a cuboid and a rectangular or a square prism.
Y3 the expectation would usually be to call it a cuboid.
You need a simple revision guide for your child, so they can do their own homework.

Sorry, not being rude! The cereal boxes/toothpaste boxes are most likely to be cuboids

www.bgfl.org/bgfl/custom/resources_ftp/client_ftp/ks2/maths/3d/index.htm

www.bbc.co.uk/schools/ks3bitesize/maths/shape_space/3d_shapes/revise2.shtml

A cuboid is the name for a particular type of prism (ie all cuboids are prisms, but not all prisms are cuboids). A cuboid could be called a rectangular (or square) prism completely correctly, but a Y3 child would be expected to know the name cuboid.

Similarly, a cube is a special type of cuboid in which all faces are square.

It's a bit like 4-sided 2D shapes. All 4 sided shapes are quadrilaterals. Some subsets of the set 'all quadrilaterals' have specific names e.g. trapezium, parallellogram, rhombus, rectangle, square. A square is a special type of rectangle, which is a special type of parallelogram, which itself is a special type of quadrilateral! It would not be incorrect to call a square a quadrilateral, but as there is a more precise name available - square - then a Y3 child would be expected to use it.

Entirely agree - unless the homework is specifically communicated as being 'a joint task for the child to do with an adult' then a Y3 child should be able to do their homework independently - if not, return it incomplete with 'X was unable to do this without support even after revising the subject using Y online site'. As a teacher, I would far rather know that a child couldn't do the homework that I had designed for them (ie has not retained whatever they have been taught which the homework is asking them to rehearse) than receive work which the parent has done for the child, wrongly giving the impression that the child does understand.

Thanks all.

I agree, HW for DS not me - but he was asking what a prism was (in my ignorance I thought it was 3D diamond), and BBC Bitesize (our usual 'go-to') did not feature a prism... His homework consisted of a page of 3D shapes and a box of 3D shape names, and he had not come across vertices/ prisms before, so wanted to find out for my own curiosity as well as his :o)

BBC BITESIZE 3D shapes

If you chopped a prism into slices, all slices would be the same size and shape (think Battenburg cake, or swiss roll).

In yr1 we introduce 'vertices' 'edges' and 'faces' to describe 3D shapes. A triangular prism is a common shape we use. Lots of re-visiting over KS1 so I'm surprised if this is new. (Unless we do things differently)

He's quite dreamy, so good chance poor teacher has done this topic to death, and he's just been practicing the 11x table in his head (current obsession...)

Great advice about feeding back to teacher the fact that there were terms/ concepts he was unsure about.

I was really interested for myself to know if there was a difference between a rectangular prism and cuboid at KS1 level. I know from arithmetic, for example, that the way I do column subtractions and the way DS is taught is quite different, so I thought I'd check for a party line on these 3D shapes!

Thanks for all the feedback.

DS, in yr 4, had a crossword to fill in with clues for names of various shapes, etc. it was really difficult, far more terminology used than was current in the 1970s when I was at school. He admits to having gone over all the terminology in class, but this type of thing bores him, so his knowledge is near zero. He had to google nearly every clue to get the answers and I joined in at the end as I wanted to learn too.

Has anyone ever used the words 'cuboid' or 'vertex' in their lives?
The curriculum for shape really gets up my nose which is why I cover it in a week near the end of the summer term. Young children have no frames of reference for these words and promptly forget them. It's just like us having to learn obscure words in French or Mandarin.

Flesh, most of us ever use most of the Maths we did at school, but some people do and there is no way to tell in advance who they might be. Simultaneous equations anyone?

Flesh! Flexy. Must get this fone phixed.

I used trigonometry once when I was trying to make a gift box... probably isn't all that common, though.

There are lots of things we teach that are pointless. Why does it matter to modern life in the Ancient Egyptians had two sun gods? Why does it matter how an ankylosaur is similar or different to a T-rex? How often do people use pictograms in real life?

In my school, we don't assess children on shape or data handling. We only assess on number and problem solving. Pros and cons.

fallen - I didn't say I didn't do it, and I think the children be revisiting shapes many times after Y2.

I do, however, think that the word roots, suffixes and prefixes (e.g. poly, quadra, tetra, lateral, angle, etc) are much more accessible to a 9-13 year old than a 5,6 or 7 year old. If these word meanings/derivations are known, then it is easy to learn the shape name.

For example: 'quadralateral' is an incredibly long and difficult word for a 7 year old to learn. An older child will know that 'quadra' means 4 and 'lateral' means sides, and will therefore have a better chance of remembering it.

I'm more against when we are required to teach it, rather than why we teach it.

Flex, point taken. Hasn't Govey got them learning ancient greek from the age of four yet?