☰ Year plan · Mathematics

Sets

Week 14 · Unit 7 · 7.1 · 4 lessons
1

Sorting into sets

Learner’s Book 1: Unit 7, pp. 97–99
GoalSort a group of things into two sets by looking for something that is the same.
New words
sort · put things that are the same togetherset · a group of things that belong togethergroup · a number of things, all together
Explanation

A group is some things all together. To sort, we look at how things are alike. Look at these shapes. We can sort them into two sets: round shapes and shapes that are not round. Both circles go in the set called round. The square and the triangle go in the set called not round. Every set needs a label, so that everybody knows the rule. Each thing belongs in only one set.

Worked examples
roundnot round
circlesquare
circletriangle
Sort the shapes into round and not round. There are 2 round shapes and 2 shapes that are not round.
two legsfour legs
hencow
duckgoat
goosesheep
Animals on a farm: a cow, a hen, a duck, a goat, a goose and a sheep. We can sort them into a set with two legs and a set with four legs. Each animal goes in one set only.
Sorting rule: ‘fruit’ and ‘not fruit’. An apple goes in fruit. A car goes in not fruit.
Class activity

Sock and spoon sort: take a handful of things from the kitchen or toy box (spoons, forks, cups; or toys). Sort them into two sets. Say your rule out loud, for example ‘spoons’ and ‘not spoons’. Can your partner guess your rule?

Practice
1
Sort into triangles and not triangles. How many triangles are there?
2
Here are two sets. What could we call each set?
3
Sort these toys into ‘has wheels’ and ‘no wheels’: car, doll, bus, ball.
4
Leo puts all the red blocks in one box and all the other blocks in another box. What is he doing?