# Focus on Math

## Helping children become mathematicians!

### Geometry Concepts: 2-D Shapes October 18, 2013

Shape and Space is one of the four strands of mathematics that is part of the BC curriculum (indeed, part of the WNCP curriculum in Canada as well). In today’s session with grade 6 teachers in SD#60, we talked about using a set of 2-D shapes in lessons involving lines, angles, etc. I first came across the shape set in a text by John Van de Walle. After printing the shapes on coloured card stock, cutting them out, laminating them, and cutting them out again, I found they could be used over and over for a variety of activities at different grade levels. Note that when doing the activities students may have a full set of shapes or a partial set. (I had personally printed full sets of the shapes in four different colours and found that to be adequate for the activities that I did).

Ideas for using the set(s) of 2-D include (but are not limited to)…

• Have students randomly chose a shape and then describe it using as many mathematical words as they can (e.g., name the shape if it has a specific name, name kinds of angles, kinds of lines, number of vertices, etc)
• Have students each select any two shapes then tell what is the same and what is different about them.
• Have students place 4 of 5 shapes in a group, all having something in common. Other try to guess the “common rule”.
• Have students randomly pick three shapes and try to find something that is the same/different for all three.
• Sort the shapes using a single rule (e.g., those with/without an acute angle; those with/without a curve ; those that are/are not regular, etc.)
• Create a large two circle Venn diagram and sort the shapes according to two rules (e.g. sort by having parallel lines and having an obtuse angle)
• Ask students to find and hold up a shape with a particular feature that you name (e.g., an obtuse angle, two pairs of parallel lines; exactly one pair of parallel lines, etc.)
• Ask students to find and hold up a shape with two particular features that you name (e.g., a right triangle, a pentagon with three obtuse angles, etc.)
• Ask students to find all shapes that have two particular features
• Students play “Shape Find” by picking one shape that is in their set to be the mystery shape (it remains on the table); then other players must ask yes/no questions to eliminate all the other shapes until only the chosen one remains.

I hope you will print off one or more of the shape sets (as needed) and try some of these activities. And please, if you have other ideas to add to the list, I’d love it if you would share those with us.

Mathematically yours,

Carollee

PS: Thanks to all the grade 6 teachers who participated in today’s session here in SD#60. There was such a lot of positive math talk going on all afternoon!

### 3 Responses to “Geometry Concepts: 2-D Shapes”

1. […] grade 1-2 class fully engaged in a geometry lesson about 2-D shapes. I had taken in my Shape Sets (which I have discussed before in a previous blog) and used those as the basis of the lesson with the […]

2. Richard Says:

Great post Carollee.

I need to check the shape set template when I get home as I think this would be a great way to talk about right prisms. I am thinking I can use your shapes and then have students classify the type of prism that would result. Students would need two copies of the shapes to “match” in order to form the base and top of the prism. This may make some nice connections between Gr 6 and 8.

• Sounds like a great extension, Richard! Be sure and let me know how it goes! I had not thought to extend the thinking from the 2-D shapes to 3-D objects. I love getting more bang for my buck!