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AAAS  :: Project 2061  :: Textbook Evaluations

Middle Grades Science Textbooks: A Benchmarks-Based Evaluation

SciencePlus: Technology and Society. Holt, Rinehart & Winston, 1997
Earth Science Life Science Physical Science

About this Evaluation Report
Content Analysis
Instructional Analysis
I. [Explanation] This category consists of criteria for determining whether the curriculum material attempts to make its purposes explicit and meaningful to students, either in the student text itself or through suggestions to the teacher. The sequence of lessons or activities is also important in accomplishing the stated purpose, since ideas often build on each other.
II. [Explanation] Fostering understanding in students requires taking time to attend to the ideas they already have, both ideas that are incorrect and ideas that can serve as a foundation for subsequent learning. This category consists of criteria for determining whether the curriculum material contains specific suggestions for identifying and addressing students’ ideas.
III. [Explanation] Much of the point of science is to explain phenomena in terms of a small number of principles or ideas. For students to appreciate this explanatory power, they need to have a sense of the range of phenomena that science can explain. The criteria in this category examine whether the curriculum material relates important scientific ideas to a range of relevant phenomena and provides either firsthand experiences with the phenomena or a vicarious sense of phenomena that are not presented firsthand.
IV. [Explanation] Science literacy requires that students understand the link between scientific ideas and the phenomena that they can explain. Furthermore, students should see the ideas as useful and become skillful at applying them. This category consists of criteria for determining whether the curriculum material expresses and develops the key ideas in ways that are accessible and intelligible to students, and that demonstrate the usefulness of the key ideas and provide practice in varied contexts.
V. [Explanation] Engaging students in experiences with phenomena (category III) and presenting them with scientific ideas (category IV) will not lead to effective learning unless students are given time, opportunities, and guidance to make sense of the experiences and ideas. This category consists of criteria for determining whether the curriculum material provides students with opportunities to express, think about, and reshape their ideas, as well as guidance on developing an understanding of what they experience.
VI. [Explanation] This category consists of criteria for evaluating whether the curriculum material includes a variety of aligned assessments that apply the key ideas taught in the material.
VII. [Explanation] The criteria in this category provide analysts with the opportunity to comment on features that enhance the use and implementation of the curriculum material by all students.

I. Providing a Sense of Purpose

Conveying unit purpose (Rating = Poor)

Each unit in SciencePlus begins with a two-page color photograph and a block of text that describes the photograph. Typically, a statement of purpose such as the following is found in this text: "In this unit, you will find that getting to know the changing nature of the Earth takes more than scientific observation and inferences-it takes imagination" (Level Green, p. 451s). This statement is not clear about the purpose of the chapters within the unit, nor is it likely to be interesting or motivating to students. Another unit begins with the following explanation:
Engineers and architects learn how to make structures more earthquake resistant by studying how the Earth's crust moves and what happens during earthquakes. In this unit you will learn about these things, too. And you will explore volcanoes, rocks, and the ancient history of our planet. [Level Red, p. 353s]

Although this purpose is more understandable, it is not likely to be interesting or motivating to students. Because both purposes are vague, most of the subsequent chapters are consistent with the purposes, but neither purpose is returned to at the end of the unit.

A component in the Annotated Teacher's Edition called Unit Focus typically suggests an opening activity or discussion for each unit. In grade six, at the beginning of Unit 8: Our Changing Earth, the Unit Focus provides two questions for the teacher to pose: "How does the Earth change?" and "How can you tell that these changes have occurred?" (Level Green, p. 450t). The teacher is to write the students' responses on the board, but no unit purpose is given in the text. In grade seven, the Unit Focus discussion for Unit 6: The Restless Earth, does include a purpose aimed at students. After discussing how two islands could have similar plants and animals but identical fossils, the teacher is to tell the students that they will "learn how islands can break apart and move and how fossils like those described can form, as well as other interesting aspects of Earth science" (p. 352t). Although students are told the purpose of the upcoming unit, the island example presented for discussion is not likely to be comprehensible to them.

The chapter introductions are somewhat different. Chapters begin with a one-page collage of photographs, pictures, diagrams, and questions. No purpose is presented, other than the implication that the chapters will help students to answer the questions.

Conveying lesson/activity purpose (Rating = Poor)

None of the lessons and only a few of the activities start with a purpose. Some activities begin with an introductory statement that does not explain what is to be done or why. For example, a sixth-grade activity that has students make cutouts of the continents and juxtapose them to make the best possible fit begins by saying: "The following Exploration puts you in the shoes of one Earth scientist who used his observations to develop a startling new theory" (Level Green, p. 459s). Similarly, another sixth-grade activity, in which students observe gravestones for signs of weathering, starts by stating, "If there is a graveyard in your community that is over 100 years old, you have the makings of an interesting project" (Level Green, p. 483s). Neither of these statements provides students with a purpose. However, some other activities offer a comprehensible purpose, such as the following: "In this activity you will make another fault model that will help explain how earthquakes occur" (Level Red, p. 363s), and "How Do Glaciers Form?.. To understand the process by which glaciers form, read the sentences below" (Level Green, p. 513s). Yet even when purposes are provided for activities, they do not link the activities to the purpose of the unit or chapter and do not engage students in thinking about what they have learned so far and what they will learn next.

Justifying lesson/activity sequence (Rating = Poor)

Each unit begins with a section in the Annotated Teacher's Edition called Unit Overview, which provides a one-sentence summary of each of the chapters in the unit (e.g., Level Green, p. 449A; Level Red, p. 351A). Such overviews do not provide a rationale for the sequence of the chapters or the topics in the chapters. For a few chapters, a rationale can be inferred-as, for example, in grade six (Green Level), where Chapter 26: Water, Wind, and Ice discusses each agent of erosion in a separate lesson. However, some chapters do not reflect a thoughtful rationale-as, for example, in grade six, Chapter 24: The Changeable Planet. It starts by introducing a variety of landforms in lesson 1.However, lesson 2 does not continue discussing landforms or how they change; rather, it explores the kinds of questions that geologists study-continental drift, plate tectonics, and continental drift again. In this lesson, students work on an activity that models plate movement (Level Green, p. 462s), even though they have not been introduced to plates yet (pp. 464-465s).

II. Taking Account of Student Ideas

Attending to prerequisite knowledge and skills (Rating = Poor)

Teachers are not alerted to specific prerequisite ideas, nor are connections made between the key ideas and their prerequisite ideas. However, some of the important prerequisite ideas are presented. In grade six, the text mentions the role of gravity in erosion (Level Green, p. 487s). It also includes an introduction to the variety of landforms on Earth. Students are to design a travel brochure for a scenic landscape that they select (pp. 454-455s) and to collect magazine photographs of landforms (p. 458t). However, even though they are told that "the answers to how landscapes have been formed can be found in the study of geology" (p. 453s), no connection is made to the part of the text (chapter 26) where the processes that change land features are discussed. The difficulties that students may have with proportionality and scale-such as slow processes and the long time frames of the Earth-are not addressed. Although students have to make several models, the role of models in science is not discussed. Lastly, the anomaly that water expands when frozen (and thus is able to wedge apart rocks, etc.) is not mentioned.

Alerting teachers to commonly held student ideas (Rating = Poor)

Although each chapter begins with what is called Prior Knowledge and Misconceptions, this component does not warn teachers about specific misconceptions that are documented in the research literature on student learning. Admittedly, the research on students' ideas in the field of Earth science is limited. Even so, this material fails to alert teachers to a well-documented student belief that the Earth is as it always has been (Freyberg, 1985). Rather, each Prior Knowledge and Misconceptions component includes the same general statement: "Your students' responses to the ScienceLog questions on this page will reveal the kind of information-and misinformation-they bring to this chapter" (e.g., see Level Red, p. 354t).

Assisting teachers in identifying their students’ ideas (Rating = Satisfactory)

Several questions throughout the chapters may provide teachers with some help in finding out their students' ideas before instruction begins. Such questions are found in components such as ScienceLog, and Prior Knowledge and Misconceptions, and are also interspersed in both the student and teacher editions. The ScienceLog questions are to be answered by students at the beginning of a chapter. Many of these questions target the key Earth science ideas, such as the following: "Has the Earth always looked like it does now?  In what ways do you think it has changed?" (Level Green, p. 452s), and, "How do you think the mountain shown on the next page was formed?" (Level Red, p. 354s). Such questions are likely to be understandable and, occasionally, to involve students in making predictions or giving explanations. Many of the questions also alert teachers to the fact that they are to be used for the purpose of finding out their students' ideas. However, there are no suggestions to teachers about how to probe beneath students' initial responses or how to interpret students' responses.

Addressing commonly held ideas (Rating = Fair)

There are a few attempts to address the commonly held student idea that the surface of the Earth is unchanging (Freyberg, 1985). For example, an end-of-the-chapter question asks students to consider all of the changes that may have occurred while Rip van Winkle slept for 20 years (Level Green, p. 492s). Another question has students predict what will happen to Niagara Falls in 50 years and in 5,000 years (Level Green, p. 476s). In grade seven, after studying erosion, students are asked to respond to the belief that, "Someday there will be no mountains to climb" (Level Red, p. 357s). These questions may help to address students' commonly held ideas, and some of the questions may even challenge their ideas.

III. Engaging Students with Relevant Phenomena

Providing variety of phenomena (Rating = Poor)

SciencePlus does not contain a sufficient number and variety of phenomena to support the different key Earth science ideas. A few phenomena are provided for five of the key Earth science ideas, but none are provided for the others. For the idea that the surface of the Earth is changing continually (Idea a), the text presents one phenomenon, namely, that the location and shape of Niagara Falls is changing constantly (Level Green, pp. 474-477s). Although it is mentioned that the Great Rift Valley of Africa will change in the future, the notion of constant change is not mentioned for this phenomenon (p. 464t).

For the idea that several processes contribute to the changing surface of the Earth (Idea b) the text presents a few phenomena. For example, it describes how moving water has eroded Niagara Falls (Level Green, pp. 474-477s), the eruption of Mount Paricutin (Level Red, p. 375s), and how the island of Surtsey formed (Level Red, p. 376s). The text also includes several descriptions of processes that shape the surface of the Earth, but typically these descriptions either do not include phenomena or do not discuss how the Earth has changed as a result of the processes.

For the idea that some Earth-changing processes are fast and some are slow (Idea d), the text presents a map that shows the changing location of Niagara Falls over the last 300 years (Level Green, p. 476s), describes a landslide in Canada moved at tremendous speed (Level Green, p. 488s), and notes how the island of Surtsey took three-and-a-half years to form from volcanic eruptions (Level Red, p. 376s).

There are no phenomena to support the idea that slow but continuous processes over time can create major changes to the surface of the Earth (Idea e). Although two changes that occur over long periods of time are referred to (namely, the formation of the Grand Canyon [Level Green, p. 472t] and the spreading of Great Rift Valley of Africa over the next few million years [Level Green, p. 464t]), the fact that small changes accumulate into visible changes over long time frames is not explained.

For the idea that matching coastlines, rocks, and fossils suggest that today's continents are separated parts of an ancient single vast continent (Idea f), the phenomena provided are not explained well enough for their significance to be appreciated (and hence for them to support the key idea). The text mentions all three of these pieces of evidence-matching coastlines, rocks, and fossils-as well as coal deposits in Antarctica, in the context of a mock debate (Level Green, pp. 460-461s). But it does not explain why such of evidence requires explanation. For example, to fully appreciate the significance of the matching fossil evidence, students need to know that these continents now have quite different climates (because they are on different latitudes), that fossils typically are found where organisms once lived, and that organisms usually only thrive in particular climates. Thus, if fossils of the same organism are found in widely separated latitudes, then it is likely that these locations formerly had the same climate. While it is possible that widely separated regions could have the same climate, the most plausible explanation for this (and other) evidence is that the regions were once in close proximity. This line of reasoning should have been provided to help students make sense of the phenomena that support Wegener's idea of continental drift. Similarly, the identical rock formations and coal in Antarctica have comparable shortcomings.

A few phenomena are presented for the key ideas that the Earth's crust consists of separate plates that are moving (Idea g) and that landforms and geologic events are caused by the motion of these plates (Idea h). For example, a photograph shows a section of the San Andreas fault and the caption explains that the fault "results from two plates sliding past one another" (Level Green, p. 464s), the Great Rift Valley of Africa is mentioned as "a spreading center" (Level Green, p. 464t), and the Atlantic Ocean is mentioned as getting wider each year (Level Green, p. 464s).

Providing vivid experiences (Rating = Poor)

Very few of the phenomena discussed in the previous criterion are explained in sufficient detail to give a vicarious sense to students. There are a few exceptions. The story about the changing shape and location of Niagara Falls is explained well. Students get to compare an early sketch of Niagara Falls to a current photograph and read about how the waterfall has changed since Europeans first came to know it in 1678. A diagram shows how the waterfall has moved in the past, and students are asked to predict where it will be in 50 years and 5,000 years (Level Green, pp. 474-477s). Using less detail but still well described, the discussion of the eruption of Mount Paricutin (Level Red, p. 375s) is likely to provide students with a sense of how the Earth changed as a result of that eruption. However, typically, other phenomena are explained in a sentence, as is the case of the Great Rift Valley is described simply as a "spreading center" (Level Green, p. 464t), which does not provide enough detail for students.

IV. Developing and Using Scientific Ideas

Introducing terms meaningfully (Rating = Fair)

An attempt is made to limit the number of terms used for the key Earth science ideas. Although the material includes some unnecessary terms, such as "esker," "fjord," "till," "terminal moraine"  (Level Green, pp. 517-518s), "composite volcano," "cinder cone," and "shield volcano" (Level Red, pp. 374-375s), they do not seem to be the focus of the lessons or to detract from the key ideas. Most of the terms introduced for these key ideas are linked to a relevant experience. For example, the terms "folds" and "faults" appear in an activity in which students have to make models with clay and compare their results with photographs of folds (Level Red, p. 361s). One problem is the introduction in grade six of the terms "plates" and "plate tectonics" (Level Green, p. 461s). These terms are used before they are defined, explained, or linked to a relevant experience. Later in grade seven, the term "plate tectonics" is introduced again, with no reference to the explanation in grade six. Although the seventh-grade text explains the term (Level Red, p. 358s), the term is still not connected to a relevant experience. Also, it should be noted that in one case a new term-namely, "hot spot"-is introduced only in an end-of-the-chapter question (Level Green, p. 468s), which is a poor technique for introducing new terms.

Representing ideas effectively (Rating = Poor)

Although there are representations for some of the key Earth science ideas, some of them are incomprehensible, mainly because they have no accompanying legend. For example, on a map of the Earth's plates, each plate is given a different color and small arrows, but these features are not explained. Assuming that the small arrows indicate the direction in which the plates are traveling, it may be confusing why some of the plates do not have arrows. Also, the plate boundary forming in Africa is not included on the map (Level Green, p. 465s).

Throughout the material, students are called upon to make models of processes (such as a convection current [Level Green, p. 462s]; a landslide [Level Green, p. 489s]; a stream table [Level Green, pp. 500-501s; 503s]; an ice flow [Level Green, p. 514s]; folds and faults [Level Red, p. 361s]; and earthquakes [Level Red, p. 363s]). None of the models involve students in thinking about how a model is like or unlike the real event or process, although, occasionally, students are asked to compare their model to a photograph (e.g., folds and faults [Level Red, p. 361s]). Some of the key Earth science ideas are not represented. Among them are that slow but continuous processes can produce significant changes in the surface of the Earth over time (Idea e) and that the surface of the Earth is changing continually (Idea a).

Demonstrating use of knowledge (Rating = Poor)

There are no demonstrations of how to use the key Earth science ideas to explain phenomena or solve problems. Although the teacher's notes include answers to student questions, these responses do not provide enough detail to model how to use the key ideas in explanations. Furthermore, since the responses are not labeled as model explanations, teachers are likely to use them in assessing student responses only, and students are not likely to hear or read the correct answers.

Providing practice (Rating = Poor)

SciencePlus is inconsistent in the amount and quality of practice it provides for the key Earth science ideas. Although it offers novel tasks for a few of the key ideas, it offers only one or none for the others. Opportunities for practice appear in several sections, such as Closure, Reteaching, Extension, and the Challenge Your Thinking questions that appear at the end of each chapter. Many practice questions focus on the ideas that the Earth's surface consists of separate plates that move (Idea g) and that landforms and geologic events result from plate motions (Idea h)-for example, "Where are most volcanoes found? How would you explain this phenomenon?" (Level Green, p. 465s) and "What would the Earth's surface be like if there were 20 smaller crustal plates instead of the existing major ones?" (Level Red, p. 359t).

Very few practice questions are provided for the idea that matching coastlines and other evidence suggest that the continents were joined long ago as a single vast continent (Idea f). For example, students are asked to rewrite a letter that they wrote earlier in the chapter to the Royal Geological Society about the evidence for continental drift, so that the revised letter contains additional information to make it more persuasive (Level Green, p. 468s).

There are a few practice questions for the idea that the Earth's surface is changing continually (Idea a). One of them asks students to write how their neighborhoods have changed in the last 300 years and how they think they will change in the next 300 years (Level Green, p. 476t). A few questions are provided for the idea that several processes contribute to changing the surface of the Earth (Idea b), namely, that students make a display showing how weathering has affected their schoolyard (Level Green, p. 485t), write a paragraph about down-slope movements (Level Green, p. 490s), and write a story or draw a picture about the formation of a volcano (Level Red, p. 380s).

No practice problems are provided for the ideas that the processes that shape the Earth today are similar to the processes that shaped the Earth in the past (Idea c), that some Earth-shaping processes are slow while others are fast (Idea d), and that slow but continuous processes can create significant changes to the surface of the Earth over time (Idea e).

V. Promoting Students' Thinking about Phenomena, Experiences, and Knowledge

Encouraging students to explain their ideas (Rating = Satisfactory)

SciencePlus routinely encourages students to explain their own ideas in components such as ScienceLog, Independent Practice, and the In-Text Questions. Often, they are asked to write their ideas, as in the following examples: "Now write two more chapters of The Niagara Story. Chapter 2 should bring the story up to the present. Chapter 3 should include your prediction of future events" (Level Green, p. 477s), and "What conditions that encourage deltas do you think exist at the mouth of this river?" (Level Green, p. 506s). Sometimes, students are asked to justify their ideas, such as when they are shown five areas next to a curvy river and are told that they have won the plot of land of their choice. Then, they are asked: "Which lot would you choose?  Why?" (Level Green, p. 502s). Mainly, students are asked to express their ideas in large group discussions, although journal writing and small group work are included, ensuring that all students can express their ideas. However, there are no suggestions to help teachers provide feedback to students or diagnose students' errors.

Guiding student interpretation and reasoning (Rating = Fair)

Most of the explorations and some of the readings are followed by questions intended to help students think about the exploration or reading. Such questions occasionally ask students to relate their observations to the key Earth science ideas, but they rarely help students to make connections between their own ideas and what they observe. Most importantly, questions are rarely structured so that they lead students gradually from observations to inferences.

For example, after reading about plate tectonics and plate motion and being presented with a diagram of the Earth's plates, students are asked questions that include the following: "To which continents was North America once joined?" and "How can you explain the coal deposits found in Antarctica?" (Level Green, p. 465s). Although these questions are both related to the idea that the Earth's continents were once joined (part of Idea f), they do not build from understanding the evidence to an understanding of the key idea. In another example, having previously read about how Niagara Falls has changed in the past, students are shown a diagram of the receding falls. Questions are provided to guide their understanding of the reading and the diagram. Furthermore, the questions are intended to lead them to the idea that Niagara Falls is changing still and will continue to move in the future (Level Green, p. 476s). But no questions help students make connections between their own ideas and what they have read. Many of the model-making activities are followed by series of questions that may guide students. For example, after students use clay to model how earthquakes occur, they are asked: "What does each block of clay represent?" "What does each layer represent?" "What is simulated by the boundary between the two clay blocks?" "What would happen to a fence that crossed the fault?" and "Compare your model with the fault in the photograph on page 361" (Level Red, p. 363s). These questions may help students understand the model better and see how it relates to the real phenomenon. However, other activities either do not provide as much guidance or ask students only to summarize what they have observed (e.g., Level Green, p. 503s).

Encouraging students to think about what they have learned (Rating = Poor)

SciencePlus begins each chapter with a ScienceLog feature that includes three or four questions about the subject of the chapter. Students respond to these questions in writing, and, at the end of the chapter, they are asked to review and "revise your original ideas so that they reflect what you've learned" (e.g., Level Green, pp. 452s, 470s, 493s). Some of these questions target the key Earth science ideas, as do the following: "How do you think the mountain shown on the next page was formed?" "Is it possible for the continents to change their location on the Earth?" and "What are some of the forces that cause the Earth to change?" (Level Red, p. 354s; Level Green, pp. 452s, 470s). These questions invite students to revise their initial ideas, but they do not ask them to think about how their ideas have changed. Furthermore, the ScienceLog questions address only a few of the key Earth science ideas.

VI. Assessing Progress

Aligning assessment to goals (Rating = Satisfactory)

For the end-of-instruction assessment, SciencePlus provides Chapter Assessment items, End-of-Unit Assessment items, and Activity Assessment items in a separate Test Generator: Test Item Listing booklet. In addition, the Challenge Your Thinking and Making Connections components in the student text are identified as end-of-chapter and end-of-unit assessment respectively (pp. T24, T60). These components of Unit 8: Our Changing Earth in Level Green (grade 6) and Unit 6: The Restless Earth in Level Red (grade 7) have been examined in terms of the first two assessment criteria. There is also an item bank that is not substantially different from the text and therefore has not been examined.

This material includes many assessment tasks that align with key Earth science ideas. However, a few of the ideas are not adequately assessed, and one key idea-the idea that Earth-shaping processes range from the very abrupt to the very slow (Idea d)-is not assessed at all.

The number of items that assess each key Earth science idea varies. For the idea that today's Earth-shaping processes are similar to those in the past (Idea c), a single item is included that has students explain the phrase, "[T]he present is the key to the past" (Level Green, p. 522st, question 2). The idea that the Earth's surface is changing continually (Idea a) is assessed with two questions: Students consider the changes that may have occurred while Rip van Winkle slept for 20 years (Level Green, p. 492st, question 4) and list evidence to convince Jerome (who believes that the Earth was always the same as it appears today) that the Earth has changed over time (Level Red, Chapter 17 Assessment, p. 274, item 5). Similarly, two items focus on the idea that several processes contribute to the changing of the Earth's surface (Idea b). Students consider what changes may have occurred while Rip van Winkle slept for 20 years (Level Green, p. 492st, question 4) and describe possible explanations for a list of observations (p. 520st, question 2). Other assessment items that appear to focus on this key idea require more specific knowledge of the processes that shape the Earth. For example, an item that has students explain "how deep trenches in the ocean floor and nearby mountain peaks are related to each other" (Chapter 24 Assessment, p. 349, item 4) requires a more sophisticated knowledge of the processes involved with the motion of plates.

A sufficient number of items are aligned with the evidence for continental drift (Idea f). All of them occur in Level Green. Students consider whether different observations support the theory of continental drift (Chapter 24 Assessment, p. 349, item 2), write a sentence using the words "continental drift" and "fossils" (Unit 8, End-of-Unit Assessment, p. 361, item 1c), write a letter to convince the Royal Geological Society to consider the idea of continental drift (pp. 459st and 468st, question 2), suggest an alternative explanation for the reptile fossils in South America and Africa (p. 468st, question 3), and list "some evidence that supports the theory of continental drift" (p. 522st, question 4). An even greater number of items are provided for the idea that the solid crust of the Earth consists of separate plates that move very slowly (Idea g) (e.g., Level Green, Chapter 24 Assessment, pp. 349-351, questions 1b, 3, 4, 5, 6, and Level Red, Chapter 16 Assessment, pp. 268-270, questions 1, 2, 3, 5, 6).

Testing for understanding (Rating = Fair)

In the introduction to SciencePlus, the Teacher's Guide states that "[t]he authors strongly discourage reliance on recall-based assessment strategies" (p. T58). Indeed, most of the assessment items provided are questions that involve the application of the key ideas, rather than questions that can be answered by rote memorization. Most items described above require application of the key Earth science ideas. However, the number of relevant application items is not consistent across the set of key ideas.

Using assessment to inform instruction (Rating = Poor)

SciencePlus emphasizes that "[a]ssessment should be ongoing" (p. T58) and claims that the Assessment component at the end of each lesson should be used "to evaluate whether students have grasped the main concepts. If you find that your students need additional help, a reteaching strategy is provided" (p. T28). However, the Reteaching components precede the Assessment components and often these components are focused on different ideas and skills.

For example, after students have been introduced to the idea of plate tectonics, the Assessment component has them create models of the Earth's interior and the Reteaching component has them use the map of the world and what they know about plate tectonics to identify ten cities that are likely to be vulnerable to earthquakes (Level Green, p. 467t). In only one instance do the Assessment and Reteaching components focus on the same key idea: the Assessment component has students decide whether statements such as, "Volcanoes can occur only in certain places," are accurate, and the Reteaching component has them explain "why earthquakes and volcanoes tend to occur in predictable locations" (Level Red, p. 378t). Furthermore, while some relevant questions are included, SciencePlus does not include suggestions for teachers about how to probe beyond students' initial responses to better understand where they are in their learning, nor does it include specific suggestions for them about how to use students' responses to make decisions about instruction.

VII. Enhancing the Science Learning Environment

Providing teacher content support (Minimal to Some support is provided.)

The material provides minimal support in alerting teachers to how ideas have been simplified for students to comprehend and what the more sophisticated versions are. Content background notes in the Annotated Teacher's Edition briefly summarize the student text at the beginning of each unit (e.g., Level Red, p. 351A, Unit Overview; Level Green, p. 449A, Unit Overview), provide a few additional related facts throughout the chapters (e.g., Level Red, p. 389t, Did You Know.; Level Green, p. 464t, Did You Know.), and give some elaboration of special features at the end of each unit (e.g., Level Red, p. 418t, Background; Level Green, p. 527t, Background). Overall, the teacher content support is brief and highly localized.

The material provides some sufficiently detailed answers to questions in the student text for teachers to understand and interpret various student responses. While the material usually provides correct, well-developed answers to questions, little additional information is provided on how to field potential student questions or difficulties (e.g., Level Red, p. 359t, Answers to An Earth-Moving Thought Experiment; Level Green, p. 485t, Answers to Questions [Simulation 3]). In addition, some answers are brief and require further explanation (for example, "Accept all reasonable responses" [Level Red, p. 364t, Homework]).

The material provides minimal support in recommending resources for improving the teacher's understanding of key ideas. While the material presents lists of references (including books, films, videotapes, software, and other media with addresses for ordering) that could help teachers improve their understanding of key ideas (e.g., "Glenn, W. H. 'Drifting: Continents on the Move.' The Science Teacher, February 1983" [Level Green, p. 449A]), the lists lack annotations about what kinds of information the references provide or how they may be helpful.

Encouraging curiosity and questioning (Some support is provided.)

The material provides a few suggestions for how to encourage students' questions but gives little support in guiding their search for answers. For example, a few tasks ask students to generate their own questions about the scientific ideas studied (e.g., Level Green, p. 456s, In-Text Question A).

The material provides many suggestions for how to respect and value students' ideas. Introductory teacher's notes about concept mapping respect and value students' ideas by stating that "there is no single 'correct' concept map" (p. T39), but also give teachers some guidance about general characteristics of good maps. In addition, students and their ideas are highlighted throughout the text. For example, photographs and dialogue balloons present students discussing scientific ideas to be studied (e.g., Level Green, p. 471s). Students are specifically referenced in some student tasks (e.g., Level Red, p. 357s, In-Text Question C). In addition, the material explicitly elicits and values students' ideas in some text passages (e.g., Level Red, p. 389s) and in many tasks. For example, teacher's notes associated with text about rock terminology respect and value students' ideas by suggesting that students develop their own definitions for terms as they work through the unit and then brainstorm as a group to develop final definitions at the end of the unit (Level Red, p. 390t, Fiery Language).

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 how they know something or to provide evidence in their responses (e.g., Level Green, p. 450t, Unit Focus; Level Green, p. 458st, In-Text Questions and Something to Think About).

The material provides many suggestions for how to avoid dogmatism. Introductory teacher's notes provide suggestions for avoiding dogmatism though the use of guiding principles such as,  "Anyone can learn science" and "Science is a natural endeavor" (p. T17). Introductory teacher's notes also explain the STS (science, technology, and society) approach of the material that "teaches science from the context of the human experience and in so doing leads students to think of science as a social endeavor" and "emphasizes personal involvement in science" (p. T35). In accordance with the introductory guiding principles, the student text portrays the nature of science as a human activity in which students participate (e.g., Level Green, p. 479st, Exploration 2), and it describes changes over time in scientific thinking (e.g., Level Red, pp. 356-358s). In addition, the material includes some text passages and special features illustrating the work of particular practicing scientists (e.g., Level Green, pp. 515-516s) and highlighting the contributions of specific cultural groups (e.g., Level Green, p. 475t, Multicultural Extension).

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, some sense of desirable student interactions may be gained from student dialogues about the scientific ideas studied (e.g., Level Red, p. 394s) and procedural directions and descriptions of student roles in cooperative group activities (e.g., Level Green, p. 484t, Cooperative Learning: Exploration 5; Level Red, p. 388t, Cooperative Learning: Exploration 3; pp. T41-T46, Cooperative Learning).

Supporting all students (Considerable support is provided.)

The material generally avoids stereotypes or language that might be offensive to a particular group. Introductory teacher's notes state that the material actively attempts to refute stereotypes by portraying "science as a rewarding, quintessentially human undertaking" and by presenting scientists as "normal people, not aloof geniuses who talk in equations" (p. T17). For example, several photographs include a diverse cultural mix of students and adults (e.g., Level Red, p. 377s; Level Green, pp. 456-457s; Level Blue, p. 237s). In addition, the material's use of multiple writing genres, including traditional expository text and some narrative forms (e.g., Level Green, p. 504s), may support the language use of particular student groups.

The material provides some illustrations of the contributions of women and minorities to science and as role models. Most of the contributions of female and minority scientists, however, appear in a few special features at the end of each unit. For example, one Science in Action feature focuses on the work of Cristy Mitchell, a female meteorologist with the National Weather Service, who uses many forms of data-including standard weather measurements such as temperature, air pressure, and wind speed along with maps, radar, and satellite imagery-to study and predict weather patterns (Level Blue, p. 287st). In addition, Multicultural Extension teacher's notes within chapters highlight specific cultural contributions related to chapter topics (e.g., Level Red, p. 380t). 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 and teacher's notes.

The material suggests multiple formats for students to express their ideas during instruction, including individual ScienceLog writing (e.g., Level Red, p. 354s, ScienceLog), cooperative group activities (e.g., Level Green, p. 452t, Prior Knowledge and Misconceptions), laboratory investigations (e.g., Level Red, p. 361st, Exploration 1), whole class discussions (e.g., Level Green, p. 453t, Getting Started), essay questions (e.g., Level Green, p. 489st, Exploration 6 and Answers to Exploration 6), concept mapping (e.g., Level Green, p. 501t, Extension), creative writing (e.g., Level Green, p. 451t, Using the Photograph), play acting (e.g., Level Red, p. 380st, item 5), visual projects (e.g., Level Red, p. 375t, Homework), and oral presentations (Level Green, p. 464t, Continental Facts). In addition, multiple formats are suggested for assessment, including individual ScienceLog revising (e.g., Level Green, p. 469st, ScienceLog), oral discussion (e.g., Level Green, p. 501t, Assessment), essay (e.g., Level Green, p. 505t, Assessment), performance (e.g., Level Red, p. 369t, Assessment), portfolio (e.g., Level Red, p. 365t, Portfolio), and visual projects (e.g., Level Green, p. 455t, Assessment). In a few instances, the material also provides a variety of alternative formats for the same task (e.g., Level Red, p. 370t, Independent Practice).

The material does not routinely include specific suggestions about how teachers can modify activities for students with special needs. However, the Annotated Teacher's Edition and supplemental resources (including review, reinforcement, and enrichment work sheets and activities with transparencies) provide additional activities and resources for students and sometimes specify ability levels. The Annotated Teacher's Edition includes a Meeting Individual Needs feature that provides activities for students related to chapter topics and specifically designated for gifted learners, second-language learners, and learners having difficulties (e.g., Level Green, p. 458t; Level Red, p. 358t). For Spanish speakers, there are English/Spanish audiocassettes, which preview each unit in both languages. Also, in the Teacher's Resource Binder and Teaching Resources there are Spanish unit summaries, work sheets, glossaries, and English and Spanish Home Connection letters, which introduce parents to each unit and provide related home activities for students to do with parents. 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 when appropriate.

The material provides many strategies to validate students' relevant personal and social experiences with scientific ideas. Some text sections relate specific personal experiences that students may have had to the presented scientific concepts (e.g., Level Red, pp. 382-383s). In addition, some tasks ask students about particular personal experiences they may have had or suggest specific experiences they could have. For example, following a classroom activity in which students identify variables affecting the flow of streams using a stream table, they are asked to locate any of the same factors affecting stream flow in their own neighborhood. After describing these factors locally, they are then asked to identify any evidence of erosion from their neighborhood stream (Level Green, p. 501st, Outside the Classroom-A Project). For a few tasks, however, the material does not adequately link the specified personal experiences to the scientific ideas being studied (e.g., Level Red, p. 391t, Closure).