Year 9 Science · Unit 4 · Lesson 13
Challenge Worksheet
Learning Goals
Odd one out
Circle the item that does not belong in each group. Then explain why it doesn't fit in the answer column.
| # | Group | Your answer (odd one + reason) |
|---|---|---|
| 1 | Dot plot Histogram Scatter plot Frequency table | |
| 2 | What is the typical height? How common is each eye colour? Does height relate to arm span? What is the median age? | |
| 3 | Positive trend Negative trend No relationship Proven cause | |
| 4 | Two numerical variables A point for each record Look for a trend Describe a single mode |
Interpret the data
A student reports...
"I plotted ten students' daily screen time (hours) against their hours of sleep. The points fall clearly from the upper left to the lower right. Therefore I have proven that using screens makes people sleep less, and the school should ban phones."
(a) Is this univariate or bivariate analysis? Identify the two variables and explain how the student should describe the trend they found.
(b) The student claims to have "proven that screens make people sleep less". Explain why a trend on a scatter plot does not prove this, suggesting one other factor that could affect both variables.
(c) Design your own bivariate investigation that could realistically be run in your classroom. State the two variables you would measure, the display you would use, what a positive and a negative trend would each look like, and one univariate question you could also answer from the same data.
Wrap Up
In one sentence, what was the main idea of this lesson?