The Method: teacher key

How to Check If Something Is True, grade 11 edition, written for 11th grade. Science checks ideas with tests, records, peer review and repeating the work. Redi's meat jars, Semmelweis's handwashing, Snow's cholera pump and Clever Hans show how a good test is built and why a result is trusted only after others can check it.

Read the book. Print this page for the key.

Questions and answers

1. What did Redi record in 1668?
   • What happened in each jar of meat (answer)
   • The date of each fly
   • How scientists voted
2. What did Semmelweis order on 15 May 1847?
   • Everyone to leave the hospital
   • Everyone to scrub with chlorinated lime between the autopsy room and the delivery room (answer)
   • Everyone to study the stars
3. Why did Pfungst use a screen in his test of Clever Hans?
   • To keep Hans from seeing the questioner's face (answer)
   • To hide the horse from the crowd
   • To make the room darker
4. What does it mean when a study cannot be replicated?
   • The scientists are probably dishonest
   • Its understanding or methods may not have been good enough (answer)
   • The study was too popular
5. What does peer review do?
   • Proves research is correct
   • Helps assure published research meets minimum standards (answer)
   • Pays scientists for their work
6. Why was the 1919 eclipse a risky test?
   • Nobody wanted the result
   • The theory forbade an outcome that could have happened (answer)
   • It could not be measured

Words

• replication: repeating a study
• peer: fellow scientist
• falsifiability: can be disproved
• confounding: mixing up
• cue: hidden signal