A line going up is only the beginning. Name the quantities, use the units, and separate the pattern from its possible cause.
Before you tell me a graph “went up,” tell me what went up. Temperature? Population? Distance? A precise description lets someone else check your claim against the data.
In this activity, you will read a line graph and write one statement it supports and one conclusion it cannot establish. The data are fictional teaching data. They are not measurements from an actual class experiment.
I can describe a pattern with measurements and units so I can make a claim the graph supports.
- I read the title, axes, units, and scale.
- I describe a change using two data points.
- I distinguish a pattern from a claim about its cause.
Read the graph before explaining it
| Time (minutes) | Water temperature (°C) |
|---|---|
| 0 | 20 |
| 5 | 25 |
| 10 | 28 |
| 15 | 30 |
Use four reading moves
- Name the quantities. Here, the horizontal axis shows time and the vertical axis shows water temperature. This activity uses a two-axis line graph; not every kind of graph has that structure.
- Check the scale. The temperature labels are 10 degrees apart. A steeper-looking line on another version might reflect a changed scale rather than a larger measured change.
- Describe the pattern. Use specific times, values, and units rather than “it increased a lot.”
- Name the limit. Ask what information is missing before explaining why the pattern happened.
Write a statement someone can check
Model: “In the fictional data, water temperature increases from 20°C at 0 minutes to 30°C at 15 minutes, a total increase of 10°C.”
You can also notice that the temperature increases by 5°C in the first five minutes but only 2°C in the last five minutes. That describes a change in the pattern. It does not tell you what caused the water to warm.
A line graph may use a vertical axis that does not begin at zero when a closer view of variation is useful. That choice should be clear. Read the actual values and labels rather than deciding from the line’s angle alone.
Your turn: What does the graph actually show?
Big question: Can you explain a graph without guessing the cause? Use the graph and data above.
Answer two questions: (1) What happens to the temperature from 5 to 10 minutes? Include the starting value, ending value, and the change in °C. (2) Does the graph prove WHY the temperature changed? Explain one piece of missing information.
Help: “From 5 to 10 minutes, the temperature changed from ___°C to ___°C, an increase of ___°C. The graph does not show ___.”
Optional stretch challenge
Compare the change from 10 to 15 minutes with the change from 5 to 10 minutes.
Finish with one revision
Read your response again and circle every number. Does each measurement have a unit? If your sentence gives a cause, mark which evidence supports that explanation. Replace an unsupported cause with a question you could investigate.
Record your work where your teacher directs. For more practice collecting and interpreting model data, try the life science virtual labs.
Science practice connection
The distinction between analyzing a pattern and establishing a cause is part of middle-school data reasoning described in NGSS: Analyzing and Interpreting Data. This short activity practices that skill; it is not a complete performance-expectation assessment.
13 Responses
Between 5 and 10 minutes, the temparature changes from 25 to 28. The graph supports quick changes , but it does not establish how much the temperature goes up.
Between 5 and 10 minutes, the water temperature changes from 25°C to 28°C. The graph supports a continuous temperature increase over time, but it does not establish that sunlight caused the warming.
Between 5 and 10 minutes, the temperature changes from 25°C to 28°C. It is a temperature rise, but it does not tell us that sunlight caused it.
Between 5 and 10 minutes, the temparature changes from 25 to 28. The graph supports quick changes , but it does not establish how much the temperature goes up.
Between 5 and 10 minutes, the water temperature changes from 25 to 28. The graph supports the temperature going up, but it does not establish why the temperature went up.
between 5 and 10 minutes, the water temperature changes from 25 to 28. The graph supports that the temperature would go up, but it dos not establish why it wont go down.
“Between 5 and 10 minutes, water temperature changes from 25°C to 28°C. The graph supports a temperature increase of 3°C, but it does not establish that sunlight caused the change.
Between 5 and 10 minutes, the temperature of the water changes from 25 to 28. The graph supports that it went up by 3, but it does not establish how fast it went up or if it ever went down during it.
The graph shows that the water got warmer over 15 minutes, going from 20°C to 30°C. From 5 to 10 minutes, the temperature went up by 3°C, and from 10 to 15 minutes it only went up by 2°C. We can tell the water got warmer, but we dont know if sunlight caused it because the graph doesnt show that. We would need more information to figure out what made the water warmer.
Between 5 and 10 minutes, the water temperature changed from 25 to 28 in the span of 5 minutes. The graph supports my answer, but it does not establish how.
Between 5 and 10 minutes, the temperature changes from 25°C to 28°C. It is a temperature rise, but it does not tell us that sunlight caused it.
Between 5 and 10 minutes, the water temperature changes from 25 to 28. The graph supports the temperature that it went up higher by 3 and from 10 to 15 minutes it went up by 2, but the graph didn’t show anything about the sun temperature so we need to gather more information.
Between 5 and 10 minutes, the water temperature changes from 25 to 28. The graph supports a temperature increase of 3 (which is slightly larger than the 2 increase seen from 10 to 15 minutes), but it does not establish that sunlight caused the change because no heat or light sources were monitored. To investigate a cause, I would want to know the physical setup of the container or have data from a control container kept in the shade.