Year 7 Science · Unit 4 · Lesson 3
Master Worksheet
Learning Goals
Read the data and conclude
A class tested how long sugar took to dissolve in water at three temperatures. They repeated each test three times and recorded the average time. Read the table and the chart, then answer the questions.
| Water temperature | Test 1 (s) | Test 2 (s) | Test 3 (s) | Average (s) |
|---|---|---|---|---|
| Cold (10 °C) | 92 | 88 | 90 | 90 |
| Warm (40 °C) | 54 | 50 | 52 | 52 |
| Hot (70 °C) | 28 | 32 | 30 | 30 |
(a) Describe the pattern in the results, then write a one-sentence conclusion that answers the question "Does temperature change how fast sugar dissolves?"
(b) Why did the class repeat each test three times and use the average, instead of testing once? Explain how this makes the evidence more trustworthy.
Plan an investigation
Scenario
A classmate claims that "loud music in the room makes plants grow taller." This is the kind of claim science can actually test. Your job is to turn the claim into a full, fair, testable investigation using the steps of the scientific process. Remember a controlled experiment changes only one thing and keeps everything else the same.
(a) Write a clear, testable question and a sensible hypothesis for this claim. State the one thing you would change and the one thing you would measure.
(b) Outline your method as a numbered list. Include what you would keep the same, how you would observe and measure systematically, how you would record results, and how you would reach a conclusion.
(c) Evaluate this statement: "If a test gives the answer you expected, it must have been a fair test." Do you agree? Justify your answer using the ideas of a controlled experiment and systematic observation.
Wrap Up
In one sentence, what was the main idea of this lesson?