How Scientists Check: teacher key

How to Check If Something Is True, grade 7 edition, written for 7th grade. Scientists do not just trust an idea, they test it. See how a horse, a pump, a hospital and jars of meat each taught people how to check a claim.

Read the book. Print this page for the key.

Questions and answers

1. What does replication mean?
   • Another scientist repeating a study to see whether the same result appears (answer)
   • A newspaper printing a story twice
   • A journal paying for an article
2. What did Pfungst find out about Clever Hans?
   • The horse could do arithmetic
   • The horse could read
   • The horse reacted to tiny signals from the person asking (answer)
3. Why is ice cream a good example of a confounding variable?
   • Ice cream causes drowning
   • Hot weather causes both ice cream sales and drownings to rise (answer)
   • Drowning causes sales
4. What happened to the death rate at Vienna's hospital after the scrubbing began?
   • It did not change
   • It fell from 12% to 1% in two years (answer)
   • It rose to 20%
5. Why was Piltdown hard to check in 1912?
   • Nobody looked at it
   • It was kept secret
   • There were no good dating methods (answer)
6. Why can a newspaper that makes a big claim need a second look?
   • It can have a reason to make it, such as selling more copies (answer)
   • Newspapers are never right
   • It has no readers

Words

• replication: repeating a test
• retraction: public correction
• variable: changing factor
• fluorine: a chemical element
• confounding: mixing up