Data and charts in Year 4 — introduction

Data and charts in Year 4 — introduction

Data and charts in Year 4

In Year 2 and Year 3 you met your first tally charts, pictographs and bar charts. The numbers were small — each tick mark or each picture was worth one. In Year 4 charts grow up. They start using scales bigger than one so they can fit large numbers on a small page, and you meet a brand-new kind: the line graph.

A quick reminder

A chart is a picture of data. It turns a list of numbers into something the eye can read at a glance.

  • Tally chart — a count, drawn as marks in groups of five.
  • Pictograph — each icon stands for a number (one, two, five, ten, …).
  • Bar chart — bars of different heights show different counts.
  • Line graph — points joined by lines, useful when something changes over time.

What's new this year

1. Bigger scales

In Year 3, a bar chart of "how many sweets does each child have" might go 0, 1, 2, 3, … up to maybe 10. In Year 4 we count crowds — "how many books were borrowed each month" — and the bars go up to 50, 100, even 1 000. Charts use a scale like 0, 5, 10, 15, … or 0, 10, 20, 30, … to fit the page.

You have to read the scale carefully before you can read the data.

2. Pictographs with a key

In Year 2 every picture was worth one. In Year 4 the key at the bottom tells you "one icon = 5" or "one icon = 10". Half an icon is worth half the key.

🍎 🍎 🍎 ½ — if the key says "🍎 = 10", this row stands for 35.

3. Comparison questions

Charts are most useful when we compare the values, not just read them one by one.

  • "Which month had the most rain?"
  • "How many more books were borrowed in March than in February?"
  • "What is the difference between the tallest and the shortest bar?"

These questions need you to read two values and then add or subtract.

4. Line graphs

A new chart this year — the line graph. The horizontal axis shows time (days, months, years), and the vertical axis shows a quantity. Each point is the value at that time, and the points are joined by straight lines.

Line graphs are perfect for showing change: temperature over a week, plant height over a month, traffic over a day.

How to read any chart

A four-step routine that works for every chart:

  1. Read the title — what does the chart show?
  2. Read the axis labels and the scale — what is being counted, and how big is each step?
  3. Read the data — find the value you need (one bar, one point, one icon row).
  4. Answer the question — sometimes just read; sometimes add, subtract or compare.

What you will learn

Try it out