3D shape sorting and treasure hunt

The theme for #mathmondayfun on Instagram this week is 3D shapes. I don't always share our weekly maths activities with a full blog, but given this is a nice activity to do if you are confined to home and many people are looking for ideas at the moment, I thought I'd share it.

Examples of 3D shapes with Magformers

The aim was to help my son start to recognise some three dimensional shapes. The ones I chose were a sphere, cylinder, cone, cube and cuboid. I helped him to understand what each shape was using 3D shapes made with our Magformers magnetic tiles; if you don't have these, just find something around the house that's the right shape. We talked about whether they had corners and which 2D shapes he could see in them e.g. a cube has six sides that are the same size of square, a cylinder has two ends which are circles but a cone only has one end that is a circle, and the sides of a cuboid are rectangles. I kept it simple and didn't mention things like not all 3D shapes with sides that are rectangles are cuboids as he's too young to understand angles.

Sorting and stacking the cylinders

Once we had talked about the 5 shapes, I showed him a selection of toys and kitchen objects which were the shapes we had discussed (the only cone I could find was a toy traffic cone which isn't a real cone shape, it's got a square base and a flat top). Tinned food mostly comes in (almost) cylindrical tins and most boxes of food are cuboids. I asked him to sort them into piles of each shape. He decided to build towers of each shape, which worked well for the cylinders, cuboids and cubes but not so well for the sole cone (which I explained wasn't a proper cone shape) or the spheres (as balls don't stack well!). He was quick at the sorting which showed he could recognise the shapes and he started to use the right names (he already knew cube and cone, but not the others), and we talked a bit about how the shapes can be very different sizes e.g. small and large cuboid boxes or flat and tall cylinders. Once he'd finished, his little brother decided it looked fun and built towers of cylinders and cuboids too, although he wasn't as good at realising that bigger ones were best near the bottom of the pile!

Shapes almost sorted

Subsequently we also did a little 'treasure hunt' for the shapes around the house. Cuboids are definitely easiest to find, but there were plenty of cylinders and spheres (we have some ball pit balls...), and quite a few cube-shaped toys. I asked him to locate one of each shape.  It didn't take long, but it did at least get him looking for the shapes.  You could make it harder by hiding single examples of each or at least making some difficult to find to occupy children for a little longer!

You could modify this 3D shape sorting and treasure hunt activity several ways depending on what you have available and the prior knowledge of your children:
- to simplify, just look for cubes or spheres (which you could call a ball shape) or even make it about 2D shapes e.g. circles, squares and triangles
- to make harder, you could add other shapes
- if you have magnetic tiles, for children with a longer attention span, you could build new shapes they don't know about together or you could even extend to making some of the shapes from cardboard to learn about nets; I will probably try this with my boys when they are older.