High School Chemistry, A Success Story?
In
the Rochester Democrat & Chronicle, November 2, 1991, a front
page feature article is headlined, Franklin teacher uses creative touch
to help chemistry sink in.
Franklin is the real name of a local high school, and while anyone who
wants to read the article may look it up, it is probably prudent that I replace
the other real names by ones invented for this article.
We'll
call the Franklin teacher Theodore Passage. A sidebar on his career explains that he is 30 years old with a
bachelor's degree in engineering, and worked as an engineer for "nearly
a year" before becoming a teacher, first in Brooklyn and now in
Rochester. His school is in a low
income neighborhood plagued with crime, drugs and dropouts. The article pictures Passage as an
enthusiastic teacher, one who understands his students, maintains order
diplomatically, livens the classes with banter, and is concerned with the progress
of his students, even visiting their parents when he sees the need. In all, a model teacher.
But what does he
teach? Here one must trust the journalist's
report:
Passage conducts a
question-and-answer session with students about the notes they've just
read.. "Allie, how do electrons
arrange themselves around atoms?" Passage asks Allie-Joe Turner, a
16-year old junior. "Shells,"
Allie says, answering correctly.
This
is what the journalist saw as successful teaching. The student got the right answer. What does this indicate about the student's understanding of
chemistry? Nothing. He "knows," to be sure, some words:
"electrons," for example.
Electrons were not known to Pasteur and Priestly, but words are not knowledge. If Allie-Joe really knew something those
scientists of one and two hundred years ago did not, one might imagine that he
would have something to tell them, were they to reappear on earth asking him
what was new in the science to which they had devoted their lives. But what he would have to tell them would be
as meaningless to them as it is to him, and to all readers of the newspaper
article as well, except for those who are scientists. Nothing in that story of electrons in
shells, as taught in high schools in Rochester, New York, would answer a single
question Priestly was wondering about in the year of his death.
Yes,
the electron shell model for the atom is of great importance, but it is not of
the same order of truth as the experimental phenomena that make it
useful. It would be more to the point for
a teacher of high school chemistry to explain what "elements" are and
why we believe there are such things, and to have the students repeat with
their own hands as nearly as possible the experiments of two centuries ago,
more or less, that led mankind to the modern conception of atom. Failing this, for it is not possible for
each student to repeat all the experience of the centuries of scientists who
preceded him, he should at least be able to describe the key experiments
and the unseen world of hypothesis they were designed to prove. Allie-Joe should learn how postulating
atoms, which nobody can see or taste, makes it easier to understand why certain
measurements come out the way they do. Electrons are a considerably more
problematic notion than atoms, but a case can be made even for them in high
school (though it seldom is). But
electron shells?
We
are a nation whose high school graduates are barely literate, half of them
unable to understand a reasoned argument of more than two sentences; a nation
split on the validity, indeed the meaning, of the theory of evolution, and
readier to believe an astrologer than the United States Surgeon General. As long as we praise the teaching of science
by incantation in this way, ignoring the very structure of science as a set of
hypotheses by which observations are bound together in a consistent,
predictable manner, we will bring up ever more generations willing to believe
in astrology, socialism and psychoanalysis.
A
grounding in the meaning of science ought to begin in Mr. Passage's class, but
what does the State of New York give this enthusiastic teacher to purvey? A catechism of "correct" answers
concerning incomprehensibles.
Nothing except jail is better calculated to stifle the imagination of
young people who might once have been induced to want to know a few of the
observable processes of nature and how they hang together. Instead, the students are divided in two
camps, the rebellious, who recognize nonsense and will have none of it, and in
the process refuse to learn anything at all, and the tractable, who go through
the motions of learning for the praise of their parents and teachers and who --
some of them -- in the fullness of time do discover, for themselves or in
college, or even later in life, that there really is knowledge out there, and
that it does have meaning. The first
group merely remains illiterate, suspicious and gullible. The second group wastes its youth. Both groups are ill served.
One
might add that chemistry is not the only subject in which a discerning
youngster will early see that he is being fed a pack of nonsense, and be
tempted to tune out. In mathematics – “Advanced
placement calculus” – he learns that the derivative of x cubed is three times x
squared. Is that wrong? No; it is
right. The trouble is that it isn't
mathematics, unless he understands what a derivative is and why anybody would
want one. Very few who come out of
today's high school calculus classes do.
That
equivalently meaningless lessons are learned in history and politics is better
understood by the general public, which sometimes demands reforms. What they get is invariably named reform,
again and again and again, but turns out only to be higher taxes for education. The need for further reform, with an
increase in “funding for education”, never dies.
One can summarize the trouble in each of these cases as a fault in the philosophy of education. Whether in physical science, social science or in the humanities, no assertion is understandable unless it is associated, at least in principle, with a statement of how we know it to be correct. Even the barest of facts should imply a question to this effect. Bach was born in 1685; how do we know this? Are there open questions in this regard? Well, actually, there aren't, but the answer to how humanity knows that date is interesting. One might along the way learn a bit about the Julian and Gregorian calendars.
Yet
the birth date of Bach is easy to understand in principle; we all know what it
means to be born, and we know how to count the days and years. Some statements are deeper than that. Consider, "Copper is an
element." Here is a statement of
some substance. What is copper,
and how do we know it is an element?
What difference would it make anywhere if the statement were
false? Could we still reconcile the
rest of chemistry with the falsity of that statement? I believe a semester devoted to that one
question, inevitably leading to ramifications into other parts of the science
of chemistry, would teach high school students a hundred times more than our present
courses do, and not only about chemistry but about the nature of knowledge
itself.
But
if we go on, before having any clear idea how it was we knew copper to be an
element and water not (Aristotle believed it was the other way round), to the statement that there are “electrons
arranged in shells” in every atom, we find ourselves far beyond any scientific
question that can be answered even in principle in a high school course. Such statements have no place at that
level. It is a disservice to the students
to tell them that this is knowledge. It
is, actually, a cargo cult.
For
in the South Pacific islands in recent times there have been recurrent
outbreaks of a sort of religious misunderstanding of the nature of European
technology, that grew out of the colonization of an unscientific society by
people with wireless radio and engine-driven ships arriving at their shores
with “cargo”. Watching the Dutch or
English invaders string up their radio antennas and turn their knobs, and
seeing all this followed by the arrival of great ships filled with marvels,
food, clothing, firearms and the like, the New Guinea natives believed they had
learned how to do all this themselves.
When the war was over and the Europeans had gone home, they strung vines
resembling antennas, turned what knobs they could find, and waited for
cargo. When it did not come they sometimes,
if they had preachers persuasive enough, destroyed all their property, to put
themselves into the same destitution the Europeans had been appeared to be
suffering before their own cargo arrived.
And so on, until the United Nations relief mission did indeed arrive
with the cargo their starvation had persuaded the world to provide.
Teaching
high school students about electron shells permits them to utter some formulas
which might fool someone in the Regents offices in Albany, but it will no more
be science or bring on its fruits than will stringing a vine result in a radio
call for cargo. (The welfare system, however, might still arrive with food
stamps.) Today's teacher is honored for doing what an ignorant school system
considers teaching: cajoling unwilling
youngsters into behaving themselves while parroting bits of meaningless
jargon called chemistry. The newspapers
may accept that sort of success as a victory over ignorance, but it is no such
thing.
It
is nothing but a feature story.
Ralph A. Raimi
3
November 1991
(slightly
revised 19 July 2008)