A pictogram is a chart that uses pictures or symbols to represent data. Pictograms usually include a key which explains what each picture or symbol represents.
Pictograms are a simple, yet engaging, way to introduce children to statistics and data handling. They build on the concepts of counting and sorting with numbers and objects, and provide a foundation for children's understanding of bar charts.
Children are expected to interpret and construct pictograms from Year 2 and to use their understanding to solve increasingly challenging problems involving pictograms throughout Key Stage Two.
Use concrete objects to start with. For example, ask children to sort toys into categories e.g. tedddies, trucks and trains. Then, introduce the idea of organising the objects into a chart in order to compare the groups more easily. As you model this process, use the vocabulary for each pictogram component (e.g. grid, axes, labels, categories, scale, interval) so children are familiar with these terms when they come to construct their own.
In Year 2, children should construct pictograms by drawing or sticking pictures on to a pre-labelled pictogram template. Often, this involves using the information provided in a simple tally chart. For maximum engagement, use data which matches the children's interests. For example, if your class love nature, ask them about their favourite animals, trees or flowers.
Moving on, children can label the intervals on a pictogram scale as they would label a number line. Deepen this understanding by using different interval values linked to skip counting. Can children label the scale in 2s, 5s and 10s? How does this change the value of the picture?
Pictograms also offer opportunities to revisit fractions. What is the value of half a picture in the pictogram? How can children use the pictogram scale to find out?
By Year 3, children should be able to construct their own pictogram template, following these five simple steps:
1. Draw the axes for your pictogram onto squared paper, using a ruler;
2. Label the scale, using appropriate intervals;
3. Label the categories (or use pictures);
4. Draw the correct number of pictures for each category into the correct column on your pictogram;
5. Add a title for your pictogram, and a key, if necessary.
This same set of skills is needed to construct bar charts.
Interpreting simple pictograms with a 1:1 ratio is simple, just count the number of pictures in each column to find the total in each category.
By Year 2, children are expected both to total and compare categorical data. Offer children plenty of opportunities to explore the pictgrams, using vocabulary, such as how many... how many more... etc. Provide children with true or false statements to solve or invite children to create their own for their partners to consider.
Greate challenge in interpreting pictograms comes when the value of the picture changes. For example, the pictures entered onto the grid may represent 2, 5, 10 or some other value. Now, children have to draw on their understanding of skip counting, repeated addition and multiplication facts or fractions.
In Year 3, children are expected to solve one-step and two-step problems involving pictograms and, by Year 4, children should be able to solve comparison, sum and difference problems involving pictograms.
In upper Key Stage Two, pictograms can explore concepts of ratio and proportion and many a KS2 SATS paper has included a question which involves intrepreting pictograms.
