Sunday, September 21, 2003

How to Pick a Science Fair Experiment

Presented is a set of intuitive classroom assignments that lead students
to pick better quality science fair projects, and in the process, teaching
them the "Scientific Process" and how it is something that they already
intuitively know.

Students are often impeded with the notion that "thinking like a scientist"
is so different from the way they normally think that they don't know how
to proceed. The given approach starts students with intuitive activities
with which they are already familiar then shows them how to merely "fine tune"
their thinking rather than viewing science as "speaking a foreign language".

In a nutshell, I propose that choosing a topic for a science fair project
and designing its experiment properly are the equivalent to the intuitive
activities of making a list of “Whenever THIS then THAT” statements and then
choosing the best “bar bet” that can be constructed from the list.

One intuitively makes observations and constructs theories to explain them
whenever a “Whenever THIS then THAT” statement is made. One intuitively
evaluates the quality of a science experiment whenever one evaluates the
quality of a bet. I.E. the same things that make a good bet make good science.
* - you think you know something about the world that the other guy
doesn’t know (otherwise he won’t take the bet if he knows it too)
* - you think you understand it well enough to explain it (otherwise it is
not a safe bet)
* - you think you can demonstrate a prediction about it (i.e. the bet itself)
in such a way that the outcome will be clear (otherwise there will be
an argument over who won the bet).
* - you have controlled the conditions of the demonstration (otherwise it
makes the outcome of the bet be affected by things you can’t predict).
* - someone else can perform the bet if need be (otherwise people will think
you’ve rigged the game).

The Approach

0) Preview the Scientific Process to students

a) observations about the world are made
b) theories are created that explain those observations
c) predictions are made from those theories
d) experiments to verify the predictions are made
e) the results of the experiments either confirm the
predictions and therefore the theory, or they don't,
in which case one goes back to (b) taking into account
the new observations made by this experiment.

0) Preview some factors that make “good science”

*) observations are new
*) observations are surprising
*) theories make predictions that can be tested
*) experiments produce results that are conclusive
*) experiments are repeatable by others

1) Observations and Theories

[Use the intuition students exhibit, to both make observations
and generate theories to explain them, whenever they use
sentences like "Whenever THIS then THAT".]

(a) Assignment 1: make a list of things you know/believe about the world

“Everyone make a list of things that they have noticed (or been told
or read) about the world.
(At least 5 things and extra credit for each extra item up to 20 items).
The items in the list should all be in one of the following forms:
* - Whenever THIS happens (or not),
then THAT seems to always happen (or not).
* - Whenever THIS situation exists (or not),
then THAT seems to always happen (or not).

Examples of form:
* - I've noticed that whenever I let go of something I'm holding,
it seems to always fall to the ground.
* - I've noticed that whenever I drop a rock in water,
it never floats.
* - I've noticed that whenever people are with their friends,
they are louder than when they are alone or with strangers.
* - I've been told that whenever plants get too much water,
they die.”

(b) follow up discussion to Assignment 1: review how students made both
observations *and* theories to explain them.
* - By putting beliefs (whether inspired by direct observation or
having been informed by others) into the form "when this then that",
it filtered out simple observations that had no theory attached.
E.G. "I noticed that the sky is usually blue" is an observation, but
there is no theory to explain it. In order to say "if A then B",
one had to already have enough of an idea about cause and effect to
make the statement, whether the statement itself was correct or not.
But people/students makes statements like this all the time and
therefore are producing theories whether they realized it or not.

2) Experiment Selection and Design

[Use the intuition students exhibit, to choose interesting science
experiments and to design them to produce a clear result, whenever
they use sentences like "I'll bet you!".]

(a) Assignment 2: make bets out of the theories

Part 1: Everyone take their list of observations, and for each one, make
a bet out of it.
* - I'll bet you that if I let go of this ball,
it will fall to the floor.
* - I'll bet you that if I throw this rock in the water,
it won't float.
* - I'll bet you that if we measure the noise level of 3 friends
eating together in the lunchroom it will be louder than if we
measure 3 people eating together that don't know each other.
* - I'll bet you that if I give this houseplant way more water
than the gardening book says it should get, it will die.

Part 2: Take your list of bets and rate each one for the factors below.
Add these factors together to get the quality score for each bet.
For safety, add the practicality factor 3 times instead of once.
The higher the score, the better the quality.
* - How non-obvious is this? (i.e. will anyone take this bet?)
Rank from 1 to 10 where 10 is "nobody knows this but me"
and 1 is "everyone on the planet knows this"
* - How well do you understand your theory (i.e. how sure of
the bet are you?). Rank from 1 to 10 where 10 means "I'm
sure I'll win the bet" and 1 means "I'm just guessing
what will happen."
* - How practical is it? (i.e. is there a way to actually
make a bet out of this?) Rank from 1 to 10 where 10 means
"this is easy to perform" and 1 means "this will take
a UN resolution to actually do."
* - How obvious will the outcome be? (i.e. how obvious will
it be who won the bet?) Rank from 1 to 10 where 10 means
"obvious result" and 1 means "we'll be in an argument
all day over who won, was it fair, is it a do-over, etc."

Part 3: Make any changes you can to the description/design of each
bet to improve its quality score before settling on the final
quality score for each bet. Take the top 3 bets and rank
each for the following factors:
* - How well can I control things that might affect the result?
(i.e. will I lose the bet because of something I can't
predict or control?). Rank from 1 to 10 where 10 means
"nothing should foul up the works if I specify when/where/
how/etc" and 1 means "every time the air conditioner
comes on it blows down my house of cards".
What conditions can be added that will make it more of a
sure bet? After adding them, make a final rank for this
* - How well can I describe the procedure? (i.e. how easy will
it be for a 3rd party to perform the bet?) Rank from 1 to
10 where 10 means "even a trained monkey could do this
correctly" and 1 means "I'm the only one who can ever
make this work".
How can the procedure and description be simplified and
improved such that others can get the same results every
time? After making the improvements, make a final rank for
this factor.

Part 4: Add the factors from part 3 to those from part 2 for the top
3 bets and pick the one with the highest quality score as your
choice for an experiment.

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