Prentice Hall Exploring
Earth Science, Exploring Life Science, and
Exploring Physical Science. Prentice
Hall School, 1997
[Explanation] This
section examines whether the curriculum material's content aligns
with the specific key ideas that have been selected for use in the
analysis. |
[Explanation] This
section examines whether the curriculum material develops an evidence-based
argument in support of the key ideas, including whether the case
presented is valid, comprehensible, and convincing. |
[Explanation] This
section examines whether the curriculum material makes connections
(1) among the key ideas, (2) between the key ideas and their prerequisites,
and (3) between the key ideas and other, related ideas. |
[Explanation] This
section notes whether the curriculum material presents any information
that is more advanced than the set of key ideas, looking particularly
at whether the “beyond literacy” information interrupts
the presentation of the grade-appropriate information. |
[Explanation] This
section notes whether the curriculum material presents any information
that contains errors, misleading statements, or statements that may
reinforce commonly held student misconceptions. |
|
Alignment
Idea a: The surface of
the Earth is changing continually.
There is a content match. The text asserts that the Earth
is changing or has changed over time in several places (pp.
278s, 324–325s, 327s, 346–347s, 434s). A typical
statement explains that, “[o]ver billions of years,
the surface of the Earth has changed many times” (p.
278s), but does not provide any concrete examples. One suggested
activity has students collect newspaper clipping about Earth-changing
events over a two-month period (p. 330st).
Idea
b: Several processes contribute to changing the
Earth’s surface.
There is a content match. While a general discussion of
processes that shape the Earth is not included, several
processes are presented (such as folding and faulting, volcanoes,
earthquakes, wind erosion, water erosion, and glacial erosion).
These processes are treated as separate topics, and are
usually found in separate chapters. The text does not indicate
that more than one process could affect the Earth at one
time or place (for example, while mountains are being built
up, they are also being eroded). Throughout this textbook,
students make models of individual processes, such as folding
mountains (p. 334s) and a stream table to show erosion (p.
476st). However, these activities and their accompanying
reading sections tend to focus on the processes, not on
the changes they bring about.
Idea
c: The processes that shape the Earth today are
similar to the processes that shaped the Earth
in the past.
There is a content match. This idea is stated once in the
text: “Hutton theorized that the processes acting
on Earth’s surface today are the same processes that
have acted on Earth’s surface in the past” (p.
595s). This statement is not further explained, and no examples,
activities, or practice questions are provided.
Idea
d: Some of the processes are abrupt, such as earthquakes
and volcanic eruptions, while some are slow, such
as the movement of continents and erosion.
There is a partial content match. The following presentation
of Idea d shows which parts of the idea are treated (in bold)
and what alternative vocabulary, if any, is used (in brackets):
Some of the processes are abrupt, such as
earthquakes and volcanoes, while some are slow,
such as the movement of continents and erosion. The text mentions
a few slow Earth-changing processes, but does not discuss
the time frame of abrupt processes. Examples of abrupt changes
are provided (such as earthquakes and volcanic eruptions),
but the focus is on the amount of damage and numbers of deaths
that occurred as a result, rather than on the abruptness of
the change. For example, photographs show the first few minutes
of the Mount Saint Helen’s 1980 eruption (p. 359s),
yet the rapid changes to the Earth (flattened mountain and
several new layers of dirt and ash on the surrounding surface)
are not mentioned in the text or caption. Slow processes,
such as erosion and mountain building, are addressed in a
few text statements. For example, the text states that “[m]ountains
are built very slowly” (p. 280s) and that it took millions
of years for the Colorado River to carve out the Grand Canyon
(p. 454s). This key idea is addressed by a few practice questions
(for example, “What is rapid mass wasting?” and
“What is slow mass wasting” [p. 456st]), but not
by any activities.
Idea
e: Slow but continuous processes can, over very
long times, cause significant changes on the
Earth’s surface.
There is no content match. Although slow Earth-changing
processes are mentioned in the text (see the discussion
of Idea d above), the text does not explain that small,
seemingly unnoticeable changes over long time frames can
result in large changes to the surface of the Earth. Students
are told that mountain building, the motion of tectonic
plates, and erosion occur over millions of years, but the
material does not state explicitly that these small changes
add up to large differences. Small yet abrupt changes, like
the mountains created by a series of earthquakes over a
period of millions of years, are not addressed.
Idea
f: Matching coastlines and similarities in rocks
and fossils suggest that today’s continents
are separated parts of what was a single vast
continent long ago.
There is a content match. This idea is presented in Chapter
12: Plate Tectonics, in the context of describing the historical
evidence for the continental drift hypothesis; namely, that
similar fossils, such as Glossopteris, and similar
rock layers have been found in now widely separated continents.
The text states, “Glossopteris fossils, which
are located in rocks about 250 million years old, are found
in South Africa, Australia, India, and Antarctica” (p.
373s). Rock evidence is presented as well: “An ancient
folded mountain chain that stretches across South Africa links
up with an equally ancient fold mountain chain in Argentina”
(p. 374s). Also, glacial features and rock deposits are provided
as evidence for continental drift as well (pp. 374–375s).
Three activities are included that could address this key
idea. In one, students tear newspaper sheets into pieces and
use the text to realign the pieces (p. 372st). This activity
includes questions that ask how putting the pieces of newspaper
back together is related to continental drift. In the second
activity, students make cutouts of the continents and try
to reassemble Pangaea (pp. 374s, 375t). The third activity
asks students to explain how Wegener’s theory made sense
of fossil evidence, and it includes practice questions about
how Wegener’s theory used each of the different kinds
of evidence (Teaching Resources, chapter 12 booklet,
p. 10).
Idea
g: The solid crust of the Earth consists of separate
plates that move very slowly, pressing against
and sliding past one another in some places, pulling
apart in other places.
There is a content match. This idea is addressed in Chapter
12: Plate Tectonics. The text provides a definition of “plate”
and discusses the theory of plate tectonics: “The word
plate refers to the moving, irregularly-shaped
slabs that fit together like paving stones to form the surface
layer of the Earth” (p. 380s). The text explains that
the plates move slowly: “Plates move at different speeds
and in different directions. Some small plates that lack landmasses
move as much as several centimeters per year. Large plates
that are weighted down with continents move only a few millimeters
per year” (p. 381s). Also, the three types of plate
boundaries (divergent, convergent, and strike-slip) are discussed
(pp. 382–383s).
Idea
h: Landforms and major geologic events, such as
earthquakes, volcanic eruptions, and mountain
building, result from these plate motions.
There is a content match. The text provides many examples
of landforms and geologic events that result from the motion
and interaction of the Earth’s plates (for example,
the Indonesian and Aleutian Islands and the Himalayan Mountains
[p. 385s]). The text also provides explanations, such as:
“The collision of plates at convergent boundaries
causes tremendous pressure and friction. Severe earthquakes
often result” (p. 382s). A few practice questions
focus on categorizing and defining plate interactions (convergent,
divergent, and strike-slip boundaries). For example, a Concept
Mastery question asks, “How do plate movements relate
to volcanoes and earthquakes?” (p. 393s, item 1).
Building
a Case
Coherence
The key ideas about the processes that shape the Earth’s
surface are addressed in
Exploring Earth Science
in five chapters (10, 11, 12, 14, and 15) in Unit 3: Dynamic
Earth. One prerequisite, namely, familiarity with land features,
is found in Chapter 8: Earth’s Landmasses in Unit 2:
Exploring Planet Earth. However, in Prentice Hall’s
modular version of
Exploring Earth Science, entitled
Prentice Hall Science, these key ideas are presented
in the Dynamic Earth module, with the prerequisite ideas about
landforms being given in a different module,
Exploring
Planet Earth. Whereas the material is presented in a
set sequence in the textbook, the corresponding modules are
unnumbered and Prentice Hall neither recommends any particular
order nor alerts teachers to what prerequisites are given
in individual modules. Consequently, it is possible for students
using the modules to study the processes that shape the Earth
before they have gained familiarity with the Earth’s
landforms.
Although many experiences and examples of most of the key
ideas are given, almost no attempt is made to tie together
all the experiences provided for any of the individual key
ideas or to relate key ideas to one another. For example,
the material presents many processes that shape the Earth
(streams, glaciers, wind, mountain building, volcanoes,
and earthquakes), but there are no statements, questions,
or activities that focus students’ attention on the
fact that several of these processes often act
at the same time on the same land feature, such as mountains
being built up at the same time erosional forces are at
work tearing them down. Furthermore, although Chapter 12:
Plate Tectonics provides examples of landforms created by
the interactions of the Earth’s plates, these examples
are not linked to the individual processes of mountain building,
volcanism, or earthquakes as described in the previous two
chapters.
Few if any relevant connections are made to ideas outside
this set of key Earth science ideas. Although this material
recommends the use of models to show Earth processes, the
opportunity to connect the use of these models to the role
of models in science is not taken.
Beyond
Literacy
The chapters examined include several topics that are
beyond science literacy as defined in
Benchmarks for Science
Literacy (
American
Association for the Advancement of Science, 1993) and
National Science Education Standards (
National
Research Council, 1996). In a few cases, more advanced
ideas are presented. For example, the discussion of moving
tectonic plates includes an explanation of magnetic evidence
for moving plates (pp. 376–380s). This discussion is
neither necessary nor likely to be comprehensible to students.
A similar problem is found with the discussion of the chemical
composition of different types of lava (pp. 357–358s).
But more often, the text explanations include so many details
of Earth-changing processes that the more general ideas are
obscured. For example, in Chapter 10: Movement of the Earth’s
Crust, students read about compression, tension, shearing,
fractures, faults, hanging walls, foot walls, normal faults,
reverse faults, thrust faults, lateral faults, folds, anticlines,
synclines, and more (pp. 328–337s). Similarly, in Chapter
15: Erosion and Deposition, students are bombarded with technical
terms that label such glacial formations as moraines, till,
drumlins, meltwater, outwash plains, and kettle lakes (pp.
466–470s). And, as students are reading about wave erosion,
their focus is diverted to such phenomena as sea cliffs, sea
terraces, sea stacks, sea caves, longshore currents, sand
bars, and spits (pp. 470–474s). Such attention to labels
and technical terms is not called for in
Benchmarks for
Science Literacy or
National Science Education Standards,
and unfortunately it will cloud the more general understanding
of how the Earth is shaped and reshaped over time.
Accuracy
The evaluation teams developed a summary assessment of
the most common kinds of errors found in each of the three
subject areas—physical science, Earth science, and life
science. In this context, “errors” is taken to
mean not only outright inaccuracies, but also those instances
in which the material is very likely to lead to or support
student misconceptions. Overall, inducement to misconstrue
is the most serious problem of accuracy in the evaluated materials.
The evaluation teams’ collective findings, presented
below, should be taken as having general applicability to
all of the evaluated materials, not complete and specific
applicability in toto to any one of them.
Identified errors occur most frequently in drawings and
other diagrams. They take the form of representations that
are likely to either give rise to or reinforce misconceptions
commonly held by students. Following are Earth science examples
of the kinds of misleading illustrative materials of most
concern to the evaluation teams:
- Maps that do not show the accurate locations of earthquakes
and volcanoes will prevent students from understanding
the relationship between these events and plate boundaries.
Likewise, diagrams and maps that do not include legends,
and photographs that do not explain the size and scale
of the object seen, are difficult for students to understand.
- Diagrams that (a) depict plates moving away from one
another, thus exposing the mantle, (b) show the mantle
very close to the surface of the Earth, or (c) show plates
as being a layer under the crust inaccurately represent
the structure of the Earth and the motion of plates.
- Diagrams that show the melting of subducted plates are
incorrect. Subducting plates are known to cause melting
in the mantle, and thus nearby volcanic activity, but
the plates do not melt.