Year 9 Science · Unit 4 · Lesson 4
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 | Named author Checkable evidence Number of shares Recent update date | |
| 2 | health.gov.au CSIRO report Peer-reviewed journal Anonymous wellness blog | |
| 3 | "Doctors are stunned" "Buy now to fix it" "Cures it overnight" "Last updated March 2025" | |
| 4 | Author Evidence Corroboration Popularity |
Which source is more reliable?
Two sources, same claim
Source A: a post on a forum called HealthTruthForum. An anonymous user writes "fluoride in tap water is poisoning us, the government is hiding it." The post has 12,000 upvotes, uses urgent language, links only to other forum posts, and was made three years ago.
Source B: a page on health.gov.au titled "Fluoride and your health." It names the government health body that wrote it, links to peer-reviewed studies, shows a "last updated" date from this year, and its conclusions match advice from the World Health Organization.
(a) Compare Source A and Source B against at least three of the six criteria. For each criterion, state how each source performs.
(b) Which source is more valid and reliable? Justify your decision by weighing several criteria together, and explain why the 12,000 upvotes on Source A do not outweigh them.
(c) A classmate says "Source B is a government page, so I can trust it completely without checking anything else." Explain why this reasoning is flawed, even though Source B is the stronger source.
Wrap Up
In one sentence, what was the main idea of this lesson?