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I'm a physics
teacher at a high school in northern With ISLE
physics, I've been able to produce a better learning experience for both
types of students. The subject becomes more engaging, challenging, and
satisfying to a wide variety of students with ISLE features in the classroom. We always start
a new topic by making observations and looking for patterns in something we
can see and touch right in front of us. Students love to make their own
investigations instead of listening to a lecture. Observations Careful
observations precisely described are a neglected essential of science, and my
students have come to find some enjoyment in this activity. They know about
the importance of a clear, concise, accurate description: a sportscaster
narrating a game, a paramedic describing symptoms, a nurse annotating a
patient's chart, an investigator at a crime scene, even a poet or novelist or
lyricist at work all need to be able to make a neutral and unambiguous
description of what they see. Students need a
lot of support and encouragement to do all the writing and sketching
necessary to make a good description. I give them a lot of praise for each
step. Initially it's
hard to separate a description of WHAT is happening from an explanation of
WHY they think it is happening. I direct their attention with questions like What can you see? But once they begin
to realize that success comes from effort they begin to relish the task. When
they realize that it's an admirable accomplishment just to clearly describe
what they can see with their own eyes, they begin to feel successful. When success is
achieved in making observations, analysis can begin with the search for
patterns. Patterns My students
learn to look for repeated similarities in observations. Sometimes patterns
are easy to detect and sometimes they are difficult. Sometimes we look for
patterns in numbers that we have determined experimentally, and sometimes we
look for a pattern in events that will guide us toward a new principle. My students
always hear me say we are practicing abilities that will make them successful
in the world after high school. Early in the year I try to find out what
field of study or career they might be interested in, and find a way to make
our studies relevant. One student wants to run a dance studio: I tell her she
needs to find patterns in numbers to figure out which classes are most
profitable; if she looks for a pattern in the steps that her students get
wrong she may discover a new principle that will make her a better
instructor. You can repeat this for any field, and most students are
impressed that you know and care about their goals for after school. When students
can find patterns, the creative work of inventing explanations begins. Explanations In my ISLE
physics, a student learns to judge an explanation by how well it matches
their own observations. Guided through carefully presented experiences, they
have the opportunity to construct their own ideas about what is really
causing the phenomena they observe in the physical world. Quantities and
terms like "force" and "atom" enter the students' lexicon
only when they have already constructed the concepts to which these terms
refer. This turns physics from an exercise in stamp-collecting (terms and
formulas memorized) into a much more lively and fun investigation. It also
makes class much more difficult for them and for me. Consider a
classroom activity that begins investigation into the kinetic molecular
theory: students must suggest explanations for why a smear of alcohol
disappears from a strip of paper. Many students
will say "the alcohol evaporates" and think this is an explanation.
From hard experience, I've learned to respond with something like "I'm proud that you know it's called
evaporation but now we are going to the next level: what is actually
happening?" Most students
think that a fancy term like "evaporation" is an explanation. It
happens with other "physics words" too. Here are some of the
questions I ask when a student presents a vocabulary term as an explanation: What does that mean? Why do you believe that? How do
you know? What did you see that makes you believe that could be true? This must be
handled carefully so as not to cause frustration. In my experience, the
students who are most susceptible to frustration in this area are those who
have been successful in traditional science classes -- and those who have
been particularly unsuccessful. A student who is
successful in ISLE physics will learn to think creatively and offer several
explanations that could account for what they see. In this example, they
might suggest that the alcohol is absorbed into the paper or into the air. It's hard for my
students to accept that their ideas are worth considering in an open forum.
But a willingness to think creatively and offer the fruits of their
deliberation to the class is essential for success. I try to
facilitate this productive atmosphere by loudly declaring my delight every
time a student pipes up with an original idea, even something silly. In the lesson of
the disappearing alcohol, if students are engaged in developing explanations,
eventually someone will volunteer a silly idea like "the alcohol
particles run away from the paper." This is a happy moment for me,
because soon enough students will learn that this is the closest idea to the
truth. With plausible Testing In my ISLE
physics, the "correct answer" is not determined by what the teacher
writes on the board or other appeals to authority. Students are correct
whenever they can justify their answer with reasoning that matches what they
see. With a list of
possible explanations, students work together to see which explanations they
can rule out. It takes students a long time to form the concept that science
makes progress not by "proving" but by "disproving". The
explanation that can't be ruled out will be our "true" explanation
only until we find new evidence that calls it into question. One of my
favorite activities to build the concept of reasoning like this is the "used car experiment". Here's the short version: Teacher:
How would you choose a used car? What questions would you ask the seller?
What would you look for? Students:
It's the right price and has a good stereo! T:
If it's the right price and has a good stereo, are you sure it's a good car? S:
No, we would want to check the mileage and the brakes and the tires! T:
What would you expect to see, if it really is a good car? S:
Low miles, working brakes, and good tires. T:
Did you ask the seller if it has a steering wheel and windshield wipers? S:
No, we assume that any car for sale has a steering wheel and windshield
wipers! T:
So if it's the right price, has a good stereo, low miles, working brakes, and
good tires, do you know for sure that it's a good car? S:
No, but we can be pretty sure! This thought
experiment is an easy way to model all the elements of a testing experiment
in a way that's familiar to every high school student. My students also love
to take any opportunity to show me their worldly sophistication, and the idea
of buying a used car is just fascinating to most of them! This is a good
opportunity to channel natural adolescent energies in a productive direction
in class. I spend a lot of
time on the Used Car Experiment, and a similar exercise we call Seventeen
TVs. Students need to practice this kind of reasoning again and again until
it becomes part of their mental toolkit: What
ideas can we rule out? Of course I have
a lot of ambitions for my course, but if students leave with only one new
idea I guess I'd like them to understand this! Reasoning In ISLE physics
in my classroom, the bulk of our unit time is spent in reasoning with the new
concepts we have constructed. I believe the best way to learn new ideas is to
use them. Can we use these new ideas to understand something we see? Do these
new ideas make sensible predictions about what will happen in novel
situations? Can we resolve apparent contradictions between our new ideas and
something else we think we know? Using
imperfectly-constructed ideas to reason about the real world is akin to
pulling yourself up by your shoelaces, but sometimes I find a way to help
students experience success in this area. Most students learn to love the
feeling of figuring something out by themselves! For me as a teacher, the
balance between challenging and supporting a student is the hardest part of
class time. The balance is different for every student and I suspect this is
a lesson I will continue to learn for the rest of my career. But just like I
tell my students: you don't have to be perfect every time in order to be
doing a good job! If you keep working, keep reflecting, and keep trying,
improvement is constant and success is inevitable! In my class we
treat learning as a process, not an end state. |
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NVESTIGATIVE
CIENCE
EARNING
NVIRONMENT
