Success criteria
- I keep fractional measurements exact on a line plot.
- I describe a line graph with values and intervals, not only “up” or “down.”
- I choose a representation that matches the type of data and question.
Learn and explain
The plot preserves quarters: 1.25 m occurs 3 times; 1.5 m occurs 2 times; 1.75 m occurs 1 time. Their combined length is 8.5 metres.
A line plot shows the distribution of separate measurements. A line graph connects values recorded in order—often over time—to show change.
| Day | Mon | Tue | Wed | Thu |
|---|---|---|---|---|
| Pages read | 18 | 21 | 20 | 27 |
Explain: Which representation would you use to show shoe sizes in a class? Which would you use for temperature each hour? Why?
Independent practice
Across the reading week, how many more pages were read on Thursday than Monday?
The change from first to last is 9 pages.
During which interval was the largest increase?
Wed to Thu increased by 7 pages.
Unfamiliar transfer — authentic data (offline first)
Collect 8–12 fractional measurements from an authentic activity: model-piece lengths, rainfall, ingredient masses, or practice times. Graph them by hand first. Write two observations and one question the graph cannot answer.
Delayed check
One week later, choose between a line plot, line graph, or bar graph for three new datasets. Defend each choice before drawing anything.
Evidence path
Save the hand-drawn graph, raw data table, and explanation to jeremy/portfolio/math/unit-6/lesson-17-represent-data/.
Next step
- Repair: if fractional positions drift, rebuild the axis with equal quarter intervals.
- Continue: if graph choice and interpretation are secure, use data to test a claim.
- Stretch: revisit mean, median, mode, and range only after the representation core is secure.