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by Steve Randak


Science's Social Context

We now have a textbook for students on the nature of science. It's intended to replace, or supplement, the inadequate first chapter of your text. It's designed to coordinate and help sequence several of the nature of science (NOS) lessons on the ENSI site. It is targeted to students in any science class, grades 7-10 (or beyond). It helps to satisfy virtually all the new NOS standards in NGSS and Common Core. If you've used any of ENSI's NOS lessons, you already know how powerful they are. This new book addresses most of the common misconceptions about NOS. It also provides information about the differences between good science, poor science, and pseudoscience. It offers clues for recognizing those differences, and opportunities to practice using those clues. "What's this magic book I've been waiting for all my life?" It's called Science Surprises: Exploring the Nature of Science. "Tell me more - like where can I see this book?" Say no more. It's available as an eBook, published with Smashwords. Click Here to get more information and a link to sample (and purchase) the new eBook Science Surprises.


 Little deceptive problem stories are presented to the class, and students are challenged to solve each problem by asking only yes/no questions. The key is for students to recognize what the False Assumption is that makes the solution tricky, and that many common problems are difficult to solve because we tend to assume a particular paradigm. Things are not always what they seem! Science is a way to work around or through those false assumptions.


Scientific knowledge is contingent and subject to modification.


Science contains an element of uncertainty.


   Students will....

1. related insights from this activity to their personal lives.
2. be unable to solve thought problems because of false assumptions.


1. Overhead projector (preferable, not required).

2. Short "stories" of events which tend to be misinterpreted due to our tendency to attach certain meanings to words. These are best printed in large letters on overhead transparencies for projection so the entire class can read them. Click Eleven Examples in pdf format to download and print. For acceptable response and false assumption made for each story, contact the webmaster using your school email address.


Minimum of 5-10 minutes per story. Can do one or more stories, depending on time available. Excellent as a "sponge" learning activity near end of a period, as long the concept of this lesson is emphasized.




Because this lesson provides an excellent opportunity to understand important elements of the Nature of Science , be sure to read our General Background Information, with our Rationale and our Approach, and tips for Presenting the lessons for maximum effect and Dispelling some of the popular myths about science.

CAUTION: Do NOT call these "False Assumption" in your classes. Instead, call them "Strange Stories." The reason for this is that some people have posted these stories AND their solutions on the internet as False Assumptions, and some clever students may Google for those solutions, thereby spoiling their use as examples of assumptions we make and to show us how hard it is to "think outside the box" or to think critically, which are skills embodied in scientific thinking.

1.  Introduce these early in the course, as part of your treatment of the nature of science. They fit nicely near the end of the period, as they are engaging and flexible in their timing.

2. Additional stories can be shared and solved at odd times throughout the course, partly as a reminder and reinforcement of the concept, and partly as something intriguing and fun. A nice way to close a period, and add variety to your class.

3. A Strong Reason for Teaching NOS: A teacher told me that his students come from very religious/conservative home schools or private schools. There is a very strong resistance to science, for both religious and political reasons. Therefore, that teacher spends a lot of time with the nature of science. He thinks that learning NOS might be one of their most important tasks. "They might forget facts, but if they can understand how science works, it will make all the difference in their lives and our community." Consequently, he was very happy to find the ENSI site.




1. Explain to students that you are going to display a short story on the overhead, and read it to them as they read along. Point out that their challenge is to solve the mystery, but they can only ask questions (one at a time) which can be answered with a "yes" or "no", and you will answer those questions truthfully. I would encourage students to begin with general questions, then narrow them down to finally asking "Is it [their conclusion]?" To those initial general question, I might answer "Not necessarily" or "Possibly."

1B. For example, with the first item (cabin on side of mountain), they could ask "Were the three people very old" and I might answer "Not necessarily - they could be." I wouldn't answer "yes" or "no" unless their question could be answered that way (for that particular story). For example, a student could finally ask "Were they killed in the cabin of an airplane when it crashed into the mountain?" To which I would reply "Yes!" If they seem stymied, suggest that they "Think outside the box; try to consider if any of the words could have different meanings."

2. Show and read the first story. Answer their "yes/no/possibly//not necessarily/" questions until someone asks the key question (the answer, phrased as a yes/no question), and you will answer "yes".

3. When it is solved, ask the class what their false assumption was. Tell the class to jot down examples of false assumptions which they/we make in our daily lives, to share with the class later. Also, ask them to think about (and record) what kinds of false assumptions people have made about the natural world, the problems this created, and how they solved the problems.

An example of this might be the illusion leading to the ancient assumption that the stars, sun, planets and moons all move around the earth. This geocentric model required the construction of complex orbits of planets and moons to explain their observed motions. Ptolemy's version (150 AD) used off-center orbits to accomplish this, but it seemed to be the most useful model for about 1400 years, even though it was based on a false assumption.

In 1543, Copernicus published his views that our planetary system should be heliocentric, with all bodies moving around the sun. He was able to show this mathematically, but he assumed that only circular orbits could be used for a perfect system (a deeply held assumption from classic Greek science), so his planetary orbits were as complex as Ptolemy's. But Galileo's discovery (1610) of phases for Venus did support the Copernican heliocentric theory. Eventually, Kepler (1619) figured out that elliptical orbits worked much better than circular orbits, so he modified the Copernican system by using elliptical orbits, resulting in the much simpler model that we have today.

Cutting through the assumptions of an earth-centered system and circular orbits has led to the modern view of our Solar System that has enabled us to predict planetary movements and fly space probes to very accurate encounters with each of our planets. Similar stories exist for the assumed causes of disease, behaviors, weather, etc. Things are not always as they seem! "Perception is NOT always REALITY!" (tipping your hat to a popular Mercedes Benz ad). I made a large banner of that "Perception..." quote and posted it in my room. It's amazing how many times arose when I conspicuously and knowingly glanced over to the poster to make the point...
For a lesson on this site that probes more deeply into this idea that "Perception is Not Always Reality" - click on that title.

4. Point out that one of the strategies of science is to recognize how easy it is to make false assumptions about the workings of nature, and to devise methods for avoiding or revealing those false assumptions for what they are. This often requires a total paradigm shift...a different way of looking at the situation, in which common assumptions are critically challenged, on purpose. Encourage your students to "think outside the box" and be cleverly creative.


There is a cabin on the side of a mountain. Three people are inside and they are dead. How did they die?

Answer: They died in an airplane crash.
The False Assumption: the cabin is a log cabin. Actually, it is the cabin of a 747 jetliner. The dead are the pilot, co-pilot, and navigator.They crashed during a snow storm.


It is hot August afternoon. The location is the living room in an old Victorian mansion. The 7-foot window is open and the curtains are blowing in the breeze generated by the thunderstorm that just passed. On the floor lie the bodies of Bill and Monica. They are surrounded by puddles of water and broken glass. Please close your eyes and picture the scene. Now change the picture. Neither Bill nor Monica has any clothing on. How did they die?

Answer: The wind blew open the windows, knocking over the fish bowl in which Bill and Monica had been swimming. The fish bowl crashed to the floor and broke, leaving Bill and Monica to suffocate without their water.
The False Assumption: that Bill and Monica were human. They were actually two goldfish.


 Have the students explain in a short paragraph the importance of this activity, and how they think it applies to the obtaining of scientific information.





1. More Scientific "False Assumptions": Here's a strategy you might try after doing a few stories in the yes/no response described above. Then tell your students we're going to try a different approach to this lesson. Read a story, then ask your students to privately think about an explanation for what happened in each "story." Have them privately write down their ideas. BUT do NOT share the "answer" provided (available from the webmaster). In fact, just say "I don't know the answer. That's just like scientists trying to understand the unknowns about the universe. There's no 'answer book.'" Those plausible explanations are what the students may eventually realize are excellent examples of "hypotheses" (which you can mention later in your NOS unit).

After they write down their ideas, you can have them share with each other in their team, then each team shares with the class what they think is the most likely answer, and WHY that is. Perhaps the class could select what they collectively think is the most likely explanation (the BEST explanation that fits all the know facts).

Next, have them suggest what information they would need to reach a solution that would explain the story with highest confidence.

The only problem is that we don't have any access to more information (more parts of the story), so testing their hypotheses in most cases is not possible in this metaphor of science.

2. Make Your Own False Assumption Stories: Later, ask students to figure out how they think these stories are developed (perhaps by thinking of words or phrases that have double meanings), then create a little story that suggests the more familiar meaning of the word rather than the privately selected hidden meaning. If given as optional homework, they can hand in their stories (one or two per student) without the hidden answer. Give them a little extra credit for creating new ones. Even more credit if it stumps the class. This then becomes an exercise in creative and outside-the-box thinking, a most valuable skill in science (and in many other jobs).

Here are a few examples:

a A man rides in on Friday, stays 3 days, then leaves on Friday. How did he do that? (ANS: "Friday" is the name of his horse.).

b. How do you get down off a duck? (ANS: You pluck it.)

c. This might be a good time to play the classic Abbott & Costello routine "Who's on first", with its hilarious use of this kind of play on words.

Click here for several more examples of puzzling statements that ENSI teacher Barbara Chisholm has shared (it was used as a quiz). And, see her suggestion for another souce of similar stories (Resources, below).

3. Here's a very clever variation you might want to try (thanks to Becky Bigley for sharing):
The way I did it is that I broke them into groups and read it aloud. Then they work together to write the evidence/facts of the "case" and then we share these together on the board. Then they give their scenarios of what they think happened and write it on the board. Then I read it again, we check their fact accumulation, and then I give them the answer and we talk about assumptions. I do it in groups of three stories, so that way I can see the impact of the exercise on their thinking during the exercise. They LOVED it. Last year I did it a little differently, I think it worked better putting it up on the board, especially for the fact collection part--they really got good at telling each other "no, there wasn't snow on the mountain" for instance. It is amazing to see how much their creative minds add into the scenarios.

[Ed. Note: I might add (as suggested earlier in #1) that to be even more scientific, don't read the answer. In science, the answer is often the "best we can do, given the evidence, for now." Your students will wail and cry and gnash their teeth. but don't give in! Instead, have them list the kinds of information (data) they would need to decide between the two or three most likely explanations. Then go to the idea above (#2) about having them build their own "False Assumption" stories.]

4. Talking about false assumptions would also be a good time to bring out natural illusions, and how science is so effective in exposing the realities of those illusions (e.g., our lesson: "Perception is Not Always Reality"). This lesson is also a good example of why we can't always use logic to answer questions about the natural world.

5. Explore some earlier misconceptions about the natural world, e.g., ...
"The continents are fixed in position, and always have been."
"The Earth is actually flat. It has 4 corners and edges." [Try our "Flat Earth" lesson ]
"Species are fixed and unchanging."
"The Earth is actually hollow. Didn't you read Journey to the Center of the Earth?"
"The Sun moves around the Earth."
"Summer is warmer because we are closer to the Sun then."
"Our Earth formed less than 10,000 years ago." [You might find helpful here this info. on "Geological Age Criticism."]

Ask students to find out where such ideas originated, and why they are no longer considered true. Discuss the evidence for this in each case.


1. For more material, get the book The Awesome Book of One-Minute Mysteries and Brain Teasers. The Kindle Edtion is currently $7.69 at Amazon.com. [Suggestion by ENSI-using teacher Mr. Kelly White.]

2. Certain commercial games (such as "Mind Trap") use stories like these. Prepare them for display (or just read them) as new stories for False Assumptions.

3. See book: Stories With Holes by Nathan Levy (vol. 1, paperback at Amazon: $9.95. For stories requiring "thinking outside the box." Rec. by teacher Barbara Chisholm.


Some of the ideas in this lesson may have been adapted from earlier, unacknowledged sources without our knowledge. If the reader believes this to be the case, please let us know, and appropriate corrections will be made. Thanks.

 1. Original Source: Steve Randak

2. Modified by:

3. ENSI / SENSI original developed by:

4. Reviewed / Edited by: Martin Nickels, Craig Nelson, Jean Beard 12/15/97

5. Edited / Revised for website by L. Flammer 8/98


 The following pages are in Adobe Acrobat pdf format in order to maintain their intended layout for showing on overhead projector. Only the first page is showing. To access all 11 pages (for printing and making transparencies), you will need to download the free Acrobat Reader from Adobe (unless it's already installed in your system). Then just click on the blue file name at the bottom of the first page. You will see the "Acrobat Exchange" application loading, then the pages will display. You might need to shift-click and drag the lower left corner of the page to enlarge it.


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