Use these steps every time you transform data into a graph or chart.
Bar charts compare separate categories, line graphs show how something changes continuously, scatter graphs show relationships between two variables, and pie charts show parts of a whole.
Check: What does your data represent? Categories, change over time, or relationships?
Label axes with the variable name and units. Start scales at zero unless there’s a good reason not to. Use equal intervals that fit all of your data comfortably.
Check: Can the smallest and largest values fit without squashing or stretching?
Mark each point precisely using a sharp pencil. Use crosses for scatter graphs, dots joined by straight segments for line graphs, and equal bar widths for bar charts. Add a key if you plot more than one set of data.
Check: Would someone else plot the same point in the same place?
Describe what the graph shows: patterns, increases/decreases, peaks, correlations, and any results that don’t fit the trend. Use numerical evidence from the graph to support your statements.
Check: Can you say what the data proves, not just what the graph looks like?
Once drawn, use your graph to answer the investigation question. Quote values (“At 50 seconds, the temperature was 42 A°C”) and describe trends (“The temperature increased steadily then levelled off”). Identify anomalies and offer possible reasons such as equipment errors or uncontrolled variables.
Graphs convert raw numbers into stories. They help scientists identify patterns quickly, communicate findings to others, and make predictions. Good graphs make your conclusions more convincing because they show the evidence behind your words.
Use a bar chart to compare average sunflower height when grown in soil, compost, and sand. Bars stay separate because each medium is a category.
Plot a line graph of water temperature against time while the beaker cools. A line graph fits because time is continuous and you measured temperature at equal intervals.
Create a scatter graph with the number of laps on the x-axis and pulse rate on the y-axis. Draw a line of best fit to show the positive correlation.
Display the proportion of paper, plastic, metal, and glass collected using a pie chart. Include a key for colours and write the percentage for each slice.
Answer all questions, then check your answers. Your quiz result is saved on this device.
× Wrong: Using a pie chart to show how temperature changes over time.
? Right: Match the graph type to the data (line graph for temperature vs time).
× Wrong: 0, 5, 6, 40 on the same axis.
? Right: Use equal intervals (0, 5, 10, 15...) so distances mean something.
× Wrong: Labeling an axis “Time” without “(s)” or “(min)”.
? Right: Always include units so data is meaningful.
× Wrong: “The line goes up and down.”
? Right: “Between 0 and 50 s, temperature rises from 20 to 40 A°C, then remains constant.”