|
THE CASE FOR
EARTH SCIENCE
By Dr. Michael
J. Passow
Earth Sciences
Correspondent
Dr. Leon
Lederman and his followers have put forth their belief that high school
students should study “Physics First.” I listened to Dr. Lederman at both the
New Jersey and New York State conferences, and came away less than convinced.
During follow-up discussions with some of his adherents, they asked me why I
feel Earth Science should precede physics. Here, then, is “The Case for Earth
Science.”
Dr. Lederman
speaks of a time traveler from the 1890s, when the American high school as we
know it was first designed. Walking to the building, the traveler is amazed by
all the technological wonders seen everywhere, but going into the science wing
of the building, feels reassured to see that little has changed since his
time. Dr. Lederman also made claims that 99% of all American high schools
teach biology, chemistry, and physics, in that order. He did not even mention
Earth Science as a high school-level course, except very briefly as a
potential senior year elective.
The Conferences
were no place for me to engage him in a debate, but much of his argument seems
based on building his version of a house of straw and then blowing it to
pieces. Most readers of this article may not even have heard his talk, so
picking out specific points would be of little value. Let me, then, set out
reasons when Earth Science makes sense as a viable alternative for one of the
first science courses for high school students.
When I took Earth
Science as a 7th-grader in 1960, much of what I was taught was
unchanged from previous decades, possibly even unchanged from Lederman’s
1890s. But although not yet in the curriculum, discoveries were being made
that revolutionized our understanding of our planet. TIROS and other
first-generation weather satellites provided new methods of observing the
ever-changing atmosphere. Astronauts began to orbit our planet, providing
exciting glimpses of surface features on scales never seen before.
Heezen,
Tharp, and their colleagues and grad students at Columbia’s then-Lamont
Geological Observatory were using sonar records to craft the physiographic
charts of the sea floors, making visible for the first time what lies hidden
beneath the ocean water. Matthews and Vine were using paleomagnetic patterns
to explain sea-floor spreading. Hess and others were adding more evidence
about how our planet acts in a dynamic system. All contributed to the
formulation of the Plate Tectonics theory, which may be considered in the
geosciences akin to the theories of evolution or atomic structure in other
areas of science.
Modern
Earth Science education began in the late 1960s with ESCP—the Earth Science
Curriculum Project. This American Geological Institute program involved
hundreds of research scientists and educators at all levels to provide
students and teachers with up-to-date information and inquiry-oriented
investigations. The hands-on lab activities and simple equipment are still
available and used three decades after ESCP ceased as a program.
Some
states, such as New York, took the best of ESCP and other programs to design a
modern curriculum and resource guide. These formed the basis for the Regents
Earth Science course that served around a hundred thousand students a year,
including many who were “tracked” into the “non-academic” programs existing in
many high schools at that time. Throughout the 1970s – 1990s, exciting new
discoveries in all areas of the Earth and Space Sciences made these classrooms
marvelous places to teach, in the true sense of the word. We might come in
each day to marvel at the latest images sent back from the Voyager spacecraft
making the “Grand Tour of the Outer Planets,” the latest images of our planet
taken with Landsat or other remote-sensing satellites, or stories about
aquanauts and research submersibles exploring the ocean floors.
In the
mid-1980s, New York State and others began to permit students in grade 8 to
“accelerate” in certain areas, and more and more schools began to provide
Earth Science for their top students as a prelude to high school study. My own
experience was that these students readily grasped the curriculum, producing
test results that most high schools would envy and beginning their studies of
biology, chemistry, and physics with a sense of how some of these areas apply
to the world around them.
By the
early 1990s, a group of New York State teachers had convinced the State
Education Department to allow them to create a “Program Modification” version
of the Regents curriculum, which included the opportunity to earn credit for
conducting a “local component” project. In some schools, this allowed students
to engage in “science fair-type” activities that greatly enhanced the
experience. However, by the late 1990s, the State Education department felt
that inequitable access to computers and other resources, as well as
variations in grading by teachers, gave some students too much of an
advantage. So, as part of the overall “reform” of science education, the New
York State Education Department superseded both the 1970 “traditional”
curriculum and the “Po-Mod” version with the current “Physical Setting: Earth
Science” core concepts and assessments. [These may be found at
www.emsc.nysed.gov/ciai, with the core concepts specifically at
http://www.emsc.nysed.gov/ciai/mst/pub/earthsci.pdf.]
Also in
the 1990s, the National Science Education Standards were produced by the
National Research Council. This document provided the main focus for our
country’s debate about what students should know and when they should know
them. Published by the National Academies Press (ISBN 0-309-05326-9), an
on-line version is available at
http://books.nap.edu/html/nses/html/index.html. The NSES included the
Earth and Space Sciences as co-equal with the “traditional” sciences for the
first time. Let us consider why.
Here’s how
the NSES begins its “Call to Action”:
This nation has established as a goal that all students should achieve
scientific literacy. The National Science Education Standards are
designed to enable the nation to achieve that goal. They spell out a vision of
science education that will make scientific literacy for all a reality in the
21st century. They point toward a destination and provide a roadmap for how to
get there. …
Achieving scientific literacy will take time because the Standards call
for dramatic changes throughout school systems. They emphasize a new way of
teaching and learning about science that reflects how science itself is done,
emphasizing inquiry as a way of achieving knowledge and understanding about
the world. They also invoke changes in what students are taught, in how their
performance is assessed, in how teachers are educated and keep pace, and in
the relationship between schools and the rest of the community--including the
nation's scientists and engineers. The Standards make acquiring
scientific knowledge, understanding, and abilities a central aspect of
education, just as science has become a central aspect of our society.
The
National Science Education Standards are premised on a conviction that all
students deserve and must have the opportunity to become scientifically
literate. The Standards look toward a future in which all Americans,
familiar with basic scientific ideas and processes, can have fuller and more
productive lives. This is a vision of great hope and optimism for America, one
that can act as a powerful unifying force in our society. We are excited and
hopeful about the difference that the Standards will make in the lives
of individuals and the vitality of the nation.
Here is part of what the creators envisions as “Goals for
School Science”:
The goals for school science that underlie the National Science
Education Standards  are to
educate students who are able to
·
experience the richness and excitement of knowing about and
understanding the natural world;
·
use appropriate scientific processes and principles in making
personal decisions;
·
engage intelligently in public discourse and debate about
matters of scientific and technological concern; and
·
increase their economic productivity through the use of the
knowledge, understanding, and skills of the scientifically literate person in
their careers.
These goals define a
scientifically literate society. The standards for content define what the
scientifically literate person should know, understand, and be able to do
after 13 years of school science.
Then, in their “Rationale” for appropriate
science content, they identify:
The eight categories of content standards are
·
Unifying concepts and processes in science.
·
Science as inquiry.
·
Physical science.
·
Life science.
·
Earth and space science.
·
Science and technology.
·
Science in personal and social perspectives.
·
History and nature of science.
They go on to explain:
The sequence of the seven
grade-level content standards is not arbitrary: Each standard subsumes the
knowledge and skills of other standards. Students' understandings and
abilities are grounded in the experience of inquiry, and inquiry is the
foundation for the development of understandings and abilities of the other
content standards. The personal and social aspects of science are emphasized
increasingly in the progression from science as inquiry standards to the
history and nature of science standards. Students need solid knowledge and
understanding in physical, life, and earth and space science if they are to
apply science.
Multidisciplinary
perspectives also increase from the subject-matter standards to the standard
on the history and nature of science, providing many opportunities for
integrated approaches to science teaching.
This does not mean that students
must first master all concepts in the areas listed earlier before proceeding
to those listed later; rather, it means that an educated individual is one who
has the ability to include concepts from all areas in evaluating information
and solving problems. In the inclusion of the Earth and Space Sciences as
co-equal, they state:
The standards for physical science, life science, and earth and space science
describe the subject matter of science using three widely accepted divisions
of the domain of science. Science subject matter focuses on the science facts,
concepts, principles, theories, and models that are important for all students
to know, understand, and use.
Recognizing realities of American school
systems, the NSES organize content not only by subject area, but also by grade
levels: K- 4, 5 – 8, and 9 – 12. The “non-subject” aspects of the content
section provide an overarching philosophy tying the various disciplines
together. Examples of how to achieve mastery of the goals uses examples from
all areas.
Extensive discussion of what can be achieved
at each level can be found in the Standards. For those like my colleagues
mentioned at the start of this essay who seriously ask what is the value of
the Earth Sciences, consider some of these statements.
For K – 4:
Young children are
naturally interested in everything they see around them--soil, rocks, streams,
rain, snow, clouds, rainbows, sun, moon, and stars. During the first years of
school, they should be encouraged to observe closely the objects and materials
in their environment, note their properties, distinguish one from another and
develop their own explanations of how things become the way they are. As
children become more familiar with their world, they can be guided to observe
changes, including cyclic changes, such as night and day and the seasons;
predictable trends, such as growth and decay, and less consistent changes,
such as weather or the appearance of meteors. Children should have
opportunities to observe rapid changes, such as the movement of water in a
stream, as well as gradual changes, such as the erosion of soil and the change
of the seasons.
For 5 – 8:
A major goal of science in
the middle grades is for students to develop an understanding of earth and the
solar system as a set of closely coupled systems. The idea of systems provides
a framework in which students can investigate the four major interacting
components of the earth system--geosphere (crust, mantle, and core),
hydro-sphere (water), atmosphere (air), and the biosphere (the realm of all
living things). In this holistic approach to studying the planet, physical,
chemical, and biological processes act within and among the four components on
a wide range of time scales to change continuously earth's crust, oceans,
atmosphere, and living organisms. Students can investigate the water and rock
cycles as introductory examples of geophysical and geochemical cycles. Their
study of earth's history provides some evidence about co-evolution of the
planet's main features--the distribution of land and sea, features of the
crust, the composition of the atmosphere, global climate, and populations of
living organisms in the biosphere. …
By grades 5-8, students
have a clear notion about gravity, the shape of the earth, and the relative
positions of the earth, sun, and moon. Nevertheless, more than half of the
students will not be able to use these models to explain the phases of the
moon, and correct explanations for the seasons will be even more difficult to
achieve.
For grades 9 – 12:
During the high school
years, students continue studying the earth system introduced in grades 5-8.
At grades 9-12, students focus on matter, energy, crustal dynamics, cycles,
geochemical processes, and the expanded time scales necessary to understand
events in the earth system. Driven by sunlight and earth's internal heat, a
variety of cycles connect and continually circulate energy and material
through the components of the earth system. Together, these cycles establish
the structure of the earth system and regulate earth's climate. In grades
9-12, students review the water cycle as a carrier of material, and deepen
their understanding of this key cycle to see that it is also an important
agent for energy transfer. Because it plays a central role in establishing and
maintaining earth's climate and the production of many mineral and fossil fuel
resources, the students' explorations are also directed toward the carbon
cycle. Students use and extend their understanding of how the processes of
radiation, convection, and conduction transfer energy through the earth
system. …
The challenge
of helping students learn the content of this standard will be to present
understandable evidence from sources that range over immense timescales--and
from studies of the earth's interior to observations from outer space. Many
students are capable of doing this kind of thinking, but as many as half will
need concrete examples and considerable help in following the multistep logic
necessary to develop the understandings described in this standard. Because
direct experimentation is usually not possible for many concepts associated
with earth and space science, it is important to maintain the spirit of
inquiry by focusing the teaching on questions that can be answered by using
observational data, the knowledge base of science, and processes of reasoning.
Consider
now the pattern of discovery for most students. As young children, they start
to become aware of their physical setting. They see hills and valleys;
experience changing weather and seasons; note the apparent movements of the
Sun, Moon, and stars; and may see on TV or personally be affected by
earthquakes, floods, and other natural hazards. Many children collect rocks,
minerals, and fossils. These form the basis for their understandings of what
makes up the world, and that most mysterious of all dimensions, Time. The
progression described above, even in its abridged form, should make a
compelling argument that comprehension of the Earth System is a valid
component of science education.
Let us now
consider similar explanations for the benefits of studying the physical
sciences. In grades K – 4:
During their early years,
children's natural curiosity leads them to explore the world by observing and
manipulating common objects and materials in their environment. Children
compare, describe, and sort as they begin to form explanations of the world.
Developing a subject-matter knowledge base to explain and predict the world
requires many experiences over a long period. Young children bring
experiences, understanding, and ideas to school; teachers provide
opportunities to continue children's explorations in focused settings with
other children using simple tools, such as magnifiers and measuring devices.
Physical science in grades
K-4 includes topics that give students a chance to increase their
understanding of the characteristics of objects and materials that they
encounter daily. Through the observation, manipulation, and classification of
common objects, children reflect on the similarities and differences of the
objects. As a result, their initial sketches and single-word descriptions lead
to increasingly more detailed drawings and richer verbal descriptions.
Describing, grouping, and sorting solid objects and materials is possible
early in this grade range. By grade 4, distinctions between the properties of
objects and materials can be understood in specific contexts, such as a set of
rocks or living materials.
For grades 5 – 8:
In grades 5-8, the focus on
student understanding shifts from properties of objects and materials to the
characteristic properties of the substances from which the materials are made.
In the K-4 years, students learned that objects and materials can be sorted
and ordered in terms of their properties. During that process, they learned
that some properties, such as size, weight, and shape, can be assigned only to
the object while other properties, such as color, texture, and hardness,
describe the materials from which objects are made. In grades 5-8, students
observe and measure characteristic properties, such as boiling points, melting
points, solubility, and simple chemical changes of pure substances and use
those properties to distinguish and separate one substance from another.
Students usually bring some
vocabulary and primitive notions of atomicity to the science class but often
lack understanding of the evidence and the logical arguments that support the
particulate model of matter. Their early ideas are that the particles have the
same properties as the parent material; that is, they are a tiny piece of the
substance. It can be tempting to introduce atoms and molecules or improve
students' understanding of them so that particles can be used as an
explanation for the properties of elements and compounds. However, use of such
terminology is premature for these students and can distract from the
understanding that can be gained from focusing on the observation and
description of macroscopic features of substances and of physical and chemical
reactions. At this level, elements and compounds can be defined operationally
from their chemical characteristics, but few students can comprehend the idea
of atomic and molecular particles.
Finally, in grades 9 – 12:
High-school students develop the
ability to relate the macroscopic properties of substances that they study in
grades K-8 to the microscopic structure of substances. This development in
understanding requires students to move among three domains of thought--the
macroscopic world of observable phenomena, the microscopic world of molecules,
atoms, and subatomic particles, and the symbolic and mathematical world of
chemical formulas, equations, and symbols.
The relationship between properties of matter
and its structure continues as a major component of study in 9-12 physical
science. … Studies of student understanding of molecules indicate that it will
be difficult for them to comprehend the very small size and large number of
particles involved. The connection between the particles and the chemical
formulas that represent them is also often not clear. …
On the basis of their
experiences with energy transfers in the middle grades, high-school students
can investigate energy transfers quantitatively by measuring variables such as
temperature change and kinetic energy. Laboratory investigations and
descriptions of other experiments can help students understand the evidence
that leads to the conclusion that energy is conserved. Although the
operational distinction between temperature and heat can be fairly well
understood after careful instruction, research with high-school students
indicates that the idea that heat is the energy of random motion and vibrating
molecules is difficult for students to understand.
The argument, then, can clearly be made
that although these physical science concepts are important, for many students
they are somewhat akin to “black box studies” because they are well outside
everyday experiences. On the other hand, if students gain familiarity with the
materials they see around them—rocks, minerals, and resources made from these
such as bricks and concrete—they may be able to construct a more effective
understanding of their physical setting. Weather affects them everyday, and
learning in an Earth Science class what causes fair and stormy weather may
provide a greater foundation for comprehending energy and mass transfer,
concepts that can later be explained more fully through classroom set-ups and
other components of a physical science course.
Another important aspect of
effective instruction involves qualified teachers. One of the largest
questions asked of proponents for “Physics First” is, “Are there enough highly
qualified teachers to provide instruction?” For both simplicity and because of
its relative importance in Earth Science education, we shall consider
statistics from New York State.
A survey by the Council of Chief
State School Officers of high school science enrollment in 2000 found that in
New York, 31% of all students were taking biology, 16% chemistry, 7% physics,
and 22% Earth Science. Of 14,057 certified Earth Science teachers nationally,
24% (3,392) were in New York, by far the greatest.
Statewide public school
statistics on a variety of factors are available at
http://www.emsc.nysed.gov/repcrd2003/statewide/total-public-cir.doc.
Examining these tables, we find that in 2002, the following results were
obtained for students taking the Regents examinations:
Physics: 43,644 (plus 578
with disabilities)—61% scoring 65 – 100
Chemistry: 92,629 (1,988
with disabilities)—67% scoring 65 -100
Living Environment: 178,197
(13,314 with disabilities)—86% scoring 65 – 100
Earth Science: 142,201
(9,523 with disabilities)—79% scoring 56 – 100
It can be seen that a movement
toward “Physics First” would involve major changes in teacher certification
and student enrollment. In order to teach the equivalent number of physics
students as Earth Science or Living Environment students, we would need,
approximately, to triple the number of certified physics teachers. At a time
when finding a sufficient number of science teachers is already difficult, is
this realistic?
I have not seen a break-down of the
schools that use the Physics First approach, but many of the proponents with
whom I have had discussions come from selective private schools or high
schools located in suburbs with relatively high socioeconomic factors. Some
educational sociologists have set forth the argument that such districts,
although classified as “public,” are not within the “mainstream” of public
education and that there is a $750,000 “admission fee” to such schools,
referring to the average home price in many of these communities. This is not
the place for a thorough consideration of this argument, but the empirical
case that Physics First would work in any community has not yet been made.
In New York State, and in much of the
country, Earth Science instruction is providing students with effective
programs leading toward mastery of the NSES and state core concepts. Should,
then, the question be asked of a program that provides Earth Science to
first-year high school students, “Is It Really Broken?” The next line, of
course, involves what to do if it’s not broken. Perhaps advocates for Physics
First might wish to explain why teaching concepts that students may or may not
be ready to master at the early high school level will be definitively better
than what can be provided through the study of Earth Science. Also, how will
the great numbers of qualified teachers become available? To make the argument
that what they believe in is better and somehow we’ll get the teachers seems
more like wishful thinking than the practical approach needed to create
generations of scientifically literate students. Meanwhile, there seems to be
a strong case for Earth Science education early in the high school science
program.
Note 1: Dr. Michael J. Passow teaches Earth
Science at the White Plains Middle School in White Plains, NY, and is
completing his 33rd year as an educator. He is also completing his
term as Past President of the Science Teachers Association of New York State,
and has twice served as President of the National Association of Geoscience
Teachers-Eastern Section. He is the founder and organizer of the “Earth2Class
Workshops for Teachers” at the Lamont-Doherty Earth Observatory of Columbia
University. For more than a decade, he has served as the Earth Science
Correspondent for the Teachers Clearinghouse. He can be reached at
michael@earth2class.org.
Note 2: This article originally appeared in
The Teachers Clearinghouse for Science and Society Education Newsletter,
v.23, no. 2 (Spring 2004), pp. 1, 20 – 24.
|
Support |
Links
