What is a Venn diagram?

Venn diagram
Venn diagrams are often used to sort data in primary school. Find out what parents need to know about how to complete and read a Venn diagram correctly, plus how they're used in the classroom in KS1 and KS2.

What is a Venn diagram?

A Venn diagram shows the relationship between a group of different things (a set) in a visual way. Using Venn diagrams allows children to sort data into two or three circles which overlap in the middle.  Each circle follows a certain rule, so any numbers or objects placed in the overlapping part (the intersection) follow both rules.

Venn diagrams in KS1

Venn diagrams encourage children to sort objects or numbers according to given criteria. Learning how to sort begins in Key Stage 1, when teachers may ask a child to sort a group of objects into two groups according to certain rules. For example, they may be given these shapes and asked to put them into either one of the following two circles:

Venn diagrams in KS2

A Venn diagram is when the two sorting circles overlap in the middle. Children need to think about how to sort something according to the two rules. For example, they might be asked to sort the numbers 5, 8, 10, 25 and 31 in the following Venn diagram:

In this example, 10 would go in the circle on the left (it's in the 5x table but not an odd number), 5 and 25 would go in the intersection (they are both part of the 5x table and odd numbers), 31 would go in the circle on the right (it's an odd number and not in the 5x table) and 8 would be outside the circles (it doesn't fit the criteria of this Venn diagram).

More advanced activities involving Venn diagrams might include reading bar charts or using their knowledge of multiples to find information to sort into a Venn diagram.

Venn diagrams are a great way to combine skills: children can practise data-handling while learning about properties of shapes or number facts.