Line graphs and timetables
Maths · Key Stage 2 · The School
What a line graph shows
A line graph plots points and joins them with a line. It is often used to show something changing over time, such as temperature through a day. The line rising means the value is going up. The line falling means it is going down. A flat, level line means the value stayed roughly the same. All three shapes are worth naming when you describe what a graph shows.
Reading a value from the line
To read the temperature at 2pm, find 2pm along the bottom of the graph. Trace a line straight up until you hit the plotted line. Then trace across to the side to read the value. Two straight lines, one up and one across, are all you need. Using a ruler for both lines keeps the reading accurate. A wobbly, hand-drawn line is where most small reading errors creep in.
Describing what the graph shows
A good description names the trend, not just single points. "The temperature rose steadily from 9am to 1pm, then stayed roughly level until 4pm" tells a reader far more than a single value ever could. Look for where the line rises, where it falls, and where it goes flat.
Reading a train timetable
A timetable lists times down a column for each stop. Find your starting stop and your finishing stop in the leftmost column. Match them to the correct column of times. Subtract the departure time from the arrival time to find the length of the journey. A train leaving at 09:15 and arriving at 09:52 takes 37 minutes.