At other times, opportunities are missed to develop real-world events and land features into phenomena. For example, Chapter 11: Plate Tectonics has many examples of land features that have resulted from the movement of tectonic plates, such as the Mid-Atlantic Ridge and the Great Rift Valley in eastern Africa (pp. 305s, 312s), the Himalayan and Appalachian mountains (p. 312s), Japan (as a volcanic island arc, p. 308s), and the San Andreas Fault (pp. 309s, 310s, 313s). All are mentioned in the text as one-sentence examples of landforms resulting from plate motions. None are explained with sufficient detail to enable students to comprehend why they provide evidence for plate motion. Also, it is likely that many students have not heard of the Great Rift Valley.

The material does not provide experiences with phenomena and then develop definitions of the terms needed to interpret those experiences. Although many terms are linked to diagrams, typically the depictions are of such poor quality that they do not clarify the meaning of the designated item. Also, central terms are introduced with only a one-sentence definition; the first time that "erosion" is mentioned in the text, for example, it is described only as "the movement of weathered material" (p. 101s). No examples, models, or illustrations are provided. The next time students encounter the term "erosion," no reference is made to the original definition. Furthermore, the text assumes that students understand what "erosion" means, as is evident in such statements as, "Erosional forces constantly change the surface of Earth, making changes in our landscape" (p. 171s). Another important term, "plate" (as in "tectonic plate"), is defined as a broken section of the Earth's crust and upper mantle (p. 304s). However, the associated diagram (Figure 11-8, showing crust, lithosphere, and asthenosphere) does not show what a plate encompasses (p. 304s).

On the other hand, some representations are accurate, comprehensible, and linked to the real thing. One such example consists of an activity that has students model different ways that natural  processes move sediments (p. 171st).

In the second instance, the text does well in using the idea that erosion occurs continually to inform decisions about where to build houses (pp. 178-179s). The section, entitled Issue: Developing Land Prone to Erosion, begins:

Some people like to live in houses and apartments on the sides of hills and mountains. Realtors say that people want to live in these places for the good view. But when you consider gravity as an agent of erosion, do you think steep slopes are safe places to live?

Then, two points of view are presented: Steep Slopes Can Be Made Safe (through carefully planted vegetation) and Building on Steep Slopes Is Dangerous (erosion occurs naturally, and some steep slopes have weak sediment layers underneath, making them prone to slumps). However, the text does not tell students that it is modeling the use of a key idea, nor does it provide appropriate running commentary (for example, note how both sides of the issue have been considered, and the science ideas that support each side have been identified).

For the idea that fossils and matching coastlines are evidence of an ancient, vast, and single continent, the textbook suggests some practice tasks, such as writing a letter in defense of Wegener's idea of continental drift (p. 297s). For the idea that the Earth is changing continuously, there are only implicit practice questions, such as calculating how far apart North America and Africa will be in 200 million years (p. 301s). Practice questions are omitted for other important and difficult Earth science ideas such as that some Earth-changing processes are fast while others are slow, and that slow but continuous processes can eventually result in a large change to the surface of the Earth.

Other opportunities for students to express their ideas, such as Science Journal, appear less regularly throughout the chapters. Science Journal gives students a chance to write their thoughts about particular topics, but there are no further directions to teachers about how to use the Science Journal feature in specific contexts, such as asking students what it would be like to go far back in time to exactly the same spot (p. 117s) or why the Himalayan mountains are growing still (p. 123s), and drawing a series of pictures that show how mountains change shape over time (p. 150t). Other features, such as Visual Learning and Inquiry Questions (in the Teacher Wraparound Edition), and Section Wrap-ups (in both the teacher and student books) seem to focus on the recall of information in the text. For example, students are asked to "[d]efine erosion and name the agents that cause it" (p. 177s) and answer the question, "How did Wegener use climate clues to support his hypothesis about continental drift?" (p. 297s). Rarely are they asked to clarify, justify, or represent their own ideas in Science Journal or other features.

The key Earth science ideas examined here are not covered adequately by assessment items. Most of the ideas are not addressed at all; for others, there are insufficient assessment items. For the end-of-instruction assessment, the material provides-in two separate resource books (Chapter Review and Assessment: Chapter and Unit Tests)-a two-page review and a four-page test for each chapter and a test for each unit. These components of chapters 7 to 11 and units 2 and 3 have been evaluated.  

Most relevant assessment items target the idea that several processes contribute to changing the Earth's surface. However, the assessments typically focus on the details of specific processes and not on the generalization that the Earth's surface is changed by several processes. Students are asked to determine "which are steeper, younger mountains or older mountains" and to explain their answers (Assessment: Chapter and Unit Tests, p. 43, Chapter 7 Test). They are to explain "why some shorelines are rocky and others have sandy beaches" (Assessment: Chapter and Unit Tests, p. 47, Chapter 8 Test), and choose the terms that complete these statements best:

A _____ is formed when water empties into a lake, gulf, or ocean. [Assessment: Chapter and Unit Tests, p. 45, Chapter 8 Test]

As Earth's plates pull apart at some boundaries, they collide at others, forming _____. [Assessment: Chapter and Unit Tests, p. 67, Chapter 11 Test]

Where plates move past one another, _____ occur. [Assessment: Chapter and Unit Tests, p. 68, Chapter 11 Test]

Seafloor spreading occurs because _____. [Assessment: Chapter and Unit Tests, p. 68, Chapter 11 Test]

For the idea that evidence suggests that today's continents are separated parts of what was a single continent long ago, the material asks students to choose the phrases that complete these statements best: "Fossils of the warm-water animal Archaeocyatha, found in Cambrian rocks of East Antarctica, suggest that _____" and "The presence of the same _____ on several continents supports the idea of continental drift" (Assessment: Chapter and Unit Tests, p. 67, Chapter 11 Test). Further, students are asked to explain why Wegener believed that "all of the continents had once been joined" and why an ocean fish fossil found on two different continents would not be good evidence of continental drift (Assessment: Chapter and Unit Tests, pp. 69-70, Chapter 11 Test).

Several questions relate to the idea that landforms and major geologic events result from plate motions.  Students are asked whether the statement, "There is no relationship between plate tectonics and volcanoes" is true and why volcanoes, "form at plate boundaries and hot spots" (Assessment: Chapter and Unit Tests, pp. 64, 66, Chapter 10 Test). They are also asked why there are many earthquakes in the Himalayas, and "how research from the Glomar Challenger helped scientists support the theory of seafloor spreading" (Assessment: Chapter and Unit Tests, p. 70, Chapter 11 Test). In addition, students are to choose the terms that complete these statements best:

As Earth's plates pull apart at some boundaries, they collide at others, forming _____.

Continental drift occurs because of _____.

Where plates move past one another, _____ occur.

Seafloor spreading occurs because _____.
[Assessment: Chapter and Unit Tests, pp. 67-68, Chapter 11 Test]

No other tasks are provided to assess students on the ideas examined here. This material does include many assessment tasks that evaluate students on their familiarity with relevant vocabulary. For example, students are to match columns of terms to their definitions, choose the terms that complete statements best (for example, "The dropping of sediments by any agent of erosion is called _____" [Assessment: Chapter and Unit Tests, p. 49, Unit 2 Test]), explain the difference between a convergent and a divergent plate boundary (Assessment: Chapter and Unit Tests, p. 67, Chapter 11 Test), and unscramble letters to reveal relevant terms. These assessment items are judged to be unaligned with the key ideas because students do not have to know any of the key ideas in order to answer them correctly.

However, the material does not include suggestions about how to probe beyond students’ initial responses or how to modify instruction according to their responses. Most significantly, it does not include sufficient quality questions that can help even an informed teacher to diagnose a student’s remaining difficulties with respect to the ideas examined.

While many of the questions can be answered by copying from the text, some questions are aligned with the key ideas. Students are asked to explain how glaciers cause erosion and to imagine finding a large rock that matches rocks normally found in Canada and account for how it got there (p. 187s); compare and contrast weathering and erosion and discuss the causes and effects of slumping (p. 198s); explain why there is no sand on many of the world’s shorelines (p. 226s); and why shorelines are changing constantly (p. 228s). Students are to describe what the Pacific ring of fire is (p. 273s) and how volcanoes and earthquakes are related (p. 290s). They are to compare and contrast continental drift and plate tectonics and divergent, convergent, and transform fault boundaries (p. 318s). They are to explain how island arcs form and why there are few volcanoes in the Himalayas but many earthquakes (p. 318s). Lastly, they are asked to discuss why a fossil of an ocean fish found on two different continents would not be good evidence of continental drift (p. 318s).

The material rarely provides sufficiently detailed answers to questions in the student text for teachers to understand and interpret various student responses. Most answers are brief and require further explanation (for example, "Students should have similar results" [p. 193t, Analyze and Apply, item 1]); often, they emphasize a "right-answer" approach (for example, "The most logical sequence of events is c, b, a, and d" [p. 195t, Skill Builder]).

The material provides minimal support in recommending resources for improving teachers' understanding of key ideas. While the material lists references that could help teachers improve their understanding of key ideas (e.g., "Lasca, Norman P. 'Build Me a River,' Earth, Jan. 1991, pp. 59-65" [p. 61T]), the lists lack annotations about what kinds of information the references provide or how they may be helpful.

The material provides a few suggestions for how to respect and value students' ideas. Introductory teacher's notes about cooperative learning state that students will "recognize.the strengths of others' [perspectives]," be presented with "the idea that there is no one, 'ready-made' answer" (p. 24T), and "respect other people and their ideas" (p. 46T). Introductory teacher's notes also state that student responses may vary in concept mapping tasks. Teachers are thus instructed to "[l]ook for the conceptual strength of student responses, not absolute accuracy" (p. 30T). In addition, Design Your Own Experiment activities are structured to be open-ended, allowing students to pursue a laboratory task in various ways. However, teacher's notes often give specific expected outcomes for these activities, which may limit their intended open-ended nature (e.g., pp. 302-303t).

The material provides a few suggestions for how to raise questions, such as, "How do we know? What is the evidence?" and "Are there alternative explanations or other ways of solving the problem that could be better?" However, it does not encourage students to pose such questions themselves. Specifically, the material includes a few tasks that ask students to provide evidence or reasons in their responses (e.g., p. 297t, Section Wrap-up, item 2; Critical Thinking/Problem Solving resource book, p. 17, item 2).

The material provides a few suggestions for how to avoid dogmatism. Introductory teacher's notes state that "[s]cience is not just a collection of facts for students to memorize" but is "a process of applying those observations and intuitions to situations and problems, formulating hypotheses, and drawing conclusions" (p. 25T). The first chapter portrays the nature of science as a human enterprise that proceeds by trial and error and uses many skills familiar to students (pp. 4-29st). Later, the material explains changes over time in scientific thinking leading to the theory of plate tectonics. But most of the text is generally presented in a static, authoritative manner with little reference to the work of particular practicing scientists, and single specific responses are expected for most student tasks.

The material does not provide examples of classroom interactions (e.g., dialogue boxes, vignettes, or video clips) that illustrate appropriate ways to respond to student questions or ideas. However, a limited sense of desirable student-student interactions may be gained from procedural directions for laboratories and cooperative group activities (e.g., pp. 192-193st, Activity 7-2; p. 237t, Activity, Interpersonal; Cooperative Learning in the Science Classroom resource book, pp. 17-18).

The material provides some illustrations of the contributions of women and minorities to science and as role models. While the introductory teacher's notes state that "[n]o single culture has a monopoly on the development of scientific knowledge" (p. 38T), most of the contributions of women and minorities appear in separate sections entitled People and Science. For example, Chapter 11: Plate Tectonics includes an on-the-job interview with a woman geologist who is working on the National Aeronautics and Space Administration's Magellan project (p. 316st). In addition, Cultural Diversity teacher notes highlight specific cultural information related to chapter topics (e.g., p. 121t). A separate Multicultural Connections resource book contains short readings and questions about individual scientists or groups addressing text-related issues in many parts of the world (e.g., Multicultural Connections, pp. 13-14). All of these sections highlighting cultural contributions are interesting and informative, but may not be seen by students as central to the material because they are presented in sidebars, supplemental materials, and teacher's notes.

The material suggests multiple formats for students to express their ideas during instruction, including individual investigations and journal writing (e.g., p. 171s, Explore Activity), cooperative group activities (e.g., p. 311t, Activity), laboratory investigations (e.g., pp. 302-303st, Activity 11-1), whole class discussions (e.g., p. 316t, Teaching Strategies), essay questions (e.g., pp. 318s, 319t, item 20), and concept mapping (e.g., p. 240st, Skill Builder). In addition, multiple formats are provided for assessment, including oral discussion (e.g., p. 297t, Assessment), essay (e.g., Assessment: Chapter and Unit Tests, p. 69, item 3), performance (e.g., p. 303t, Assessment), and portfolio (e.g., p. 227t, Assessment Portfolio). However, the material does not usually provide a variety of alternatives for the same task (except in rare instances for special needs students).

The material does not routinely include specific suggestions about how teachers can modify activities for students with special needs. However, the Teacher Wraparound Edition and supplemental Program Resources (including reinforcement and enrichment work sheets, a study guide, and activities with transparencies) provide additional activities and resources for students of specific ability levels. At the beginning of each chapter, teacher's notes link the various chapter activities to different learning styles (e.g., p. 200t, Learning Styles). Several of the visual-spatial activities are also coded LEP for students with limited English proficiency (e.g., p. 296t, Visual Learning). For Spanish speakers, there are English/Spanish audiocassettes, which summarize the student text in both languages, and a Spanish Resources book, which translates key ideas and activities for each chapter. Teacher's notes about Meeting Individual Needs at the beginning of the Teacher Wraparound Edition highlight the importance of providing "all students with a variety of ways to learn, apply, and be assessed on the concepts" (p. 39T). However, the placement of supplemental resources in individual booklets separate from the main text may discourage their use, and the special needs codes within chapters may discourage teachers from using those activities with all students. Also, a few of the activities suggested for students with special needs are not well suited for the intended students (e.g., p. 192t, Inclusion Strategies).

The material provides some strategies to validate students' relevant personal and social experiences with scientific ideas. Many text sections begin with a brief reference to a specific personal experience students may have had that relates to the presented scientific concepts (e.g., p. 236s). In addition, some tasks ask students about particular personal experiences they may have had or suggest specific experiences they could have. For example, Community Connection teacher notes suggest that students photograph locations in their local community where water erosion has taken place (p. 207t). However, the material rarely encourages students to contribute relevant experiences of their own choice to the science classroom and sometimes does not adequately link the specified personal experiences to the scientific ideas being studied (e.g., p. 196s, Science Journal). Overall, support is brief and localized.