Physics First
Leon M. Lederman
For the past five years I have been campaigning to
change the way science is taught in U.S. high schools [1]. In the vast
majority of high schools, students' introduction to disciplinary science
starts in ninth grade with biology. About 50% of students go on to
a year of chemistry and one in four will take a third year of sciencethe
dreaded physics. The sequence goes back about 100 years and is based
upon the notion that physics is the most abstract and mathematical
of subjects and should wait for some intellectual maturity and mathematical
experience.
With the advent of science standards as promulgated
by NSES [2] and AAAS [3], there is a strong move towards installing
a three-year science and three-year mathematics requirement.
Now it is my firm conviction that the existing situation
is pedagogically dumb; the subjects are not connected, ninth grade
biology is a turn-off with a huge number of new words to memorize,
very descriptive with very little if any of the syntheses that characterize
the way science works. If there is any doubt, please see the article
by Professor Uri Haber-Schaim that analyzes a variety of high school
textbooks [4].
With the existence of standards, we have the opportunity
of rethinking this sequence and crafting a core science curriculum
of three or four years, suitably blended with mathematics. The current
political recognition of the importance of education and in particular
of science education offers the opportunity of achieving substantial
reforms in how we teach science.
There is no reason why ninth grade physics cannot
be made into an exciting and influential gateway to the study of scienceall
of science. If we truly love and feel passionate about physics,
we should be proud to consider changing our style and accepting this
obligation to introduce our subject to all high school students.
Perhaps it would help to imagine that, in our freshman classes, there
are future chemists, biologists, neurosurgeons, congressmen, journalists,
TV anchors, voters . . . as well as future AP physics students who
may be turned off from science by ninth grade biology.
I have been told by good high school physics teachers
that, "we don't do freshmen!" Yet, physics teachers know
that physics supplies the underpinning of much of chemistry and of
molecular biology. Harold Varmus, Nobel Laureate, eminent biologist
and former head of NIH, has continuously emphasized the need of modern
biology for a strong physics [5].
We have organized ARISE [7] (American Renaissance
In Science Education) to address the problem of a new curriculum. ARISE
would suggest that the core sequence be arranged so that ninth grade
is Conceptual Physics, using only the algebra that is being learned
in eighth and ninth grade. Physics, largely mechanics, electricity
and magnetism, is concrete, practical, dealing with issues and examples
which may be drawn from real life just outside the classroom. As is
well known, Conceptual Physics [6] is not easy to teach, but the degree
of mathematics included is clearly adjustable and would depend on local
circumstances.
However, the last month or so of physics would introduce
atoms, their qualitative electrical structure, the relevant forces,
and some introduction to the quantum nature of atomic structure. Molecules
are studied as stable combinations of atoms, perhaps with reference
to potential energy curves. The transition to tenth grade chemistry
should be seamless with the productive repetition of atomic structure
and binding from the chemistry point of view.
Chemistry is "the science of change," the
study of the properties of substances and of the reactions that create
new substances from old. Chemical change occurs constantly in the ordinary,
visible world of daily life and has overwhelming practical importance.
It is, however, best understood by reference to a rarely seen microscopic
world of atoms and molecules. The two levels (macroscopic and microscopic)
interact constantly in the modern practice of chemistry. The curriculum
presents chemistry as a discipline that discovers, on the microscopic
level, an underlying unity in the wildly diverse macroscopic changes
that condition our lives [7].
Simple chemical bonding theory, electronegativity,
electrons and electron dot structures lead to molecular geometries
in three dimensions and the introduction to molecular biology. We are
now in eleventh grade biology. In this physics-first approach, students
are well grounded in the basics of atomic structure and molecular interactions.
This enables the teacher to emphasize how structure naturally supports
function. For example, many molecules form polymers: What differentiates
one type of polymer from another? How are these fundamental components
used in various combinations leading to the diversity of life? The
appreciation of simple principles derived in physics and chemistry
enables the students to understand the natural rise of complexity.
This course begins with the molecule and progresses
to the cell, on to the organism and finally to the ecosystem. Everything
in the course is connected to survival (natural selection). Reproduction
is explored at a genetic level, and then content moves to the environmental
level.
Understanding the structure and function of the cellthe
basic building block of lifeis the optimal way for students to understand
life at and beyond the level of an organism. Treating cells as the
fundamental unit, the curriculum asks: Why are cells useful? How do
they respond to changes? What do they need to function properly? What
consequences arise from improper functioning? Similar questions can
be applied to the organism and the ecosystem. A high school biology
course should also include enough human biology to equip students for
making informed decisions about their lives.
Overall, this approach aims at enabling students to
become decision-makers in an ever-changing world, a world where the
tools of molecular biology are so powerful that humans have the unprecedented
ability to alter both themselves and the environment that sustains
them.
Issues connecting the disciplines are many, e.g. conservation
of energy and energy states, vibrations from simple harmonic motion
to microwave spectroscopy, photoelectric effect to photosynthesis,
and, most importantly, the nature of science thinking. I believe this
new, coherent curriculum can be made to blend in components of science
process: how does it work, why is science different from other fields
of learning, how do we know these things, some history and the need
for skepticism, openness, the need for verification.
Societal issues should also be dispersed through the
curriculum. Hands-on, experimental components, inquiry, the lessons
of cognition science must also be blended in. Clearly fewer topics
will be covered and subjects which link the sciences should receive
priority.
The net result will be high school seniors with a
respect and enthusiasm for science, equipped for lifetime with a science
way of thinking. Senior year can have a rich offering of the applications
of their core knowledge, especially to earth and space science, but
also to environmental science, to science, technology and society (STS),
or to the array of AP courses in each of the core disciplines. In general,
the senior year should be a year in which the three years of high school
work are integrated and applied in interdisciplinary projects. In a
more ideal world, college admissions, usually done in December, would
be conditional to the successful completion of the senior year program.
The new sequence has large requirements for new resources:
new teaching materials, extensive and continuous professional development,
regular meetings of the teachers of sciences to coordinate their course
work, enrich examples, seek connections and, perhaps most visionary,
include in these conferences the teachers of the arts, humanities and
social sciences to present the future citizen with a sense of the unity
of knowledge.
Implementing this program faces very impressive obstacles.
However, we have located over 100 high schools around the nation that
have installed various versions of "physics first". Many
of these schools have very positive experiences with this "kinder,
gentler (and more logical)" introduction to science. The crucial
issue is: Can we get schools to change? It is fortunate that physicists
suffer the genetic defect of optimism.
What can physics teachers do? I believe they should
join this campaign for a rational science sequence as part of a science
core curriculum. There are clearly all kinds of variations on the scheme
I outlined. The act of fixing this glaring defect in our schools may
well permit even more dramatic reforms in our schools. It should propagate
change down into middle schools and up to college science courses.
In this 21st century, we need a seamless science education, internally
coherent and in harmony with the social sciences and the humanities,
stretching from pre-K to grade 16.
Suggestions and advice from the physics community
would be very welcome.
References
1. Leon M. Lederman, "A
Science Way of Thinking" Education Week Vol. XVIII, No.
40 June 16, 1999.
2. National Science
Education Standards, NRC (National Academy Press, Washington
DC 1996)
3. American Association for the Advancement of Science, Project 2061, Benchmarks for
Science Literacy
4. U. Haber-Schaim, "In My OpinionHigh School Physics Should be
Taught Before Chemistry and Biology," The Physics Teacher, Vol .22,
p. 330, 1984
5. The Impact
of Physics on Biology and Medicine, APS News-The Back Page,
August/September 1999
6. Conceptual Physics textbooks include: (1) Conceptual Physics,
Hewitt; (2) Concepts in Physics, Hobson; (3) Physics, A World View,
Kirkpatrick and Wheeler
7. Framework, ARISE,
Fermi National Accelerator Laboratory (1998)
Leon M. Lederman is the Director
Emeritus of Fermilab, and holds an appointment as Pritzker Professor
of Science at the Illinois Institute of Technology. The Nobel Prize-winning
physicist is a founder and resident scholar at the Illinois Mathematics and Science Academy in
Aurora, Ill., a public residential high school for the gifted. He
is also a founder and the Chairman of the Teachers
Academy for Mathematics and Science in Chicago.
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