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A picture graph uses pictures or symbols to show data. Each symbol stands for one object (or sometimes more). Picture graphs are concrete and visual, making them ideal for first graders to read and create.
You've seen picture graphs before and know that they use little pictures instead of numbers to show information. Now you're going to learn both how to read a picture graph carefully and how to make one yourself.
When you read a picture graph, the first thing to do is look at the key (sometimes called a legend). The key tells you what each picture stands for. If a picture graph shows what pets people have and each cat picture stands for 1 cat, then 3 cat pictures means 3 cats. But if the key says each picture stands for 2 animals, then 3 pictures means 6 animals! Always check the key before you count anything. You already know how to use tally charts to count things — the key is like the tally chart's rule for what each mark is worth.
Now look at the categories — the different rows or columns. Each row is a different group (like dogs, cats, fish). To find out how many are in each category, you count the pictures in that row. Once you know the totals for each category, you can compare them. Which row has the most pictures? Which has the fewest? How many more does the biggest row have than the smallest? These comparison questions are what picture graphs are designed to help you answer quickly, because you can see the difference just by looking at the lengths of the rows.
To make a picture graph, you start by collecting your data — counting how many of each thing you have. This is where a tally chart comes in handy. Once you have your totals, you draw one picture for each item (or however many the key says). Line up your pictures neatly in rows so they're easy to count. Give your graph a title so readers know what it's showing. And don't forget the key! Without the key, no one knows what each picture represents.
A well-made picture graph tells a story about data at a glance. When you get to bar graphs in later grades, you'll notice they do the same job as picture graphs — comparing amounts across categories — but use bars instead of pictures. All the skills you're building now (reading a key, comparing categories, asking "how many more?") will carry right into those more advanced graphs.