Bar charts and time graphs
Interpret and present discrete and continuous data using appropriate graphical methods, including bar charts and time graphs
What a learner can do afterwards
- Read a time graph showing temperature changes over a day
- Present data about plant growth over weeks as a time graph
- Explain the difference between a bar chart (discrete) and a time graph (continuous)
1 · Read
A bar chart uses bars to compare separate groups, like how many children like each colour. Each bar's height shows a number. Taller bars mean bigger numbers.
A time graph is different. It shows something changing over time, like the temperature during a day. Instead of separate bars, you draw a line that moves up and down as the number changes.
A gardener measures her plant every week. Week 1 it is 2 cm, week 2 it is 5 cm, week 3 it is 9 cm. She draws a time graph with a line that climbs higher each week, showing the plant growing.
Ask yourself: are these separate groups, or is something changing over time? Separate groups, like favourite colours, need a bar chart. Change over time, like temperature or growth, needs a time graph.
Bar charts compare separate groups with bars, and time graphs show change over time with a connecting line.
2 · Watch
Take it off screen
Where it sits
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.