The text does not provide experiences together with phenomena and then develop definitions of the terms needed to interpret these experiences. However, in introducing definitions, it typically includes references to everyday experiences either immediately before or after the definition.

New words seem to be introduced unnecessarily. For example, the section Our Atmosphere—A Sea of Air opens with a reference to a common difficulty: “You can see right through it, and most of the time you can’t even feel it. But the air we breathe and live in contains many gas particles…” (p. 229s). Rather than address the basic issue of “Is air matter?” that is known to cause students difficulties (e.g., Lee et al., 1993), the text moves on quickly to describe the levels of the atmosphere: the troposphere, stratosphere, mesosphere, and thermosphere. Such detailed vocabulary is unnecessary at this level.

Often, the text goes beyond the vocabulary and concepts recommended for middle grades students by including the names of the gas laws (e.g., Boyle’s and Charles’s on pages 229–230s) and the terms “heat of vaporization” and “heat of fusion” (p. 226s) without instructing teachers that these terms could be introduced—if they must be used at all—after students have a thorough understanding of the concepts behind them.

There are no representations that focus on the idea that matter is made of particles (rather than that it contains particles), no representations that will help students to appreciate how tiny the particles are, and no representations of the processes of changes of state at the particulate level.

Although some inaccuracies are evident in the representations, they are fewer and less severe than those in the other textbooks evaluated. For instance, whereas in the other textbooks, balls representing molecules are misleadingly shown in different colors, in this text the balls look the same (blue) in the solid, liquid, and gaseous states—only their arrangement changes (e.g., p. 217s).

Students are given some opportunities to practice the key ideas, including a few novel tasks. Several tasks ask students to make drawings or to describe the arrangement and motion of particles that make up specific substances. Fewer tasks require students to explain phenomena using the kinetic molecular theory. There are no practice tasks related to the very small size of particles.

In the student text, practice tasks are located in the Section Wrap-up and the Chapter Review features. Several sections in the Teacher Wraparound Edition—Extensions, Reteach, Skill Builders, and Assessment—contain questions that can be used for student practice. However, as the teacher’s notes do not explicitly suggest using the questions for student practice, their use for this purpose depends on the teacher.

There are some occasions for students to express their own beliefs in relation to the key ideas. More opportunities are provided for students to express ideas in general, but they are not appropriate with respect to the key physical ideas. For example, consider this Science Journal task:

A glass of water and a puddle of water, both containing the same volume of water at the same temperature, are left to evaporate. Which do you think will evaporate sooner? In your Science Journal, write and explain your answer. [p. 227s]

Questions posed in figure captions could be used to have students express their ideas; however, there are no specific instructions to teachers about how to use these questions. They may be answered by one student only as part of a class discussion (which means that many students in the class will not even think about the question) or not at all.

The Science Journal is the only means given in the text to ensure that each student expresses her or his conceptions, but it is not used very often, particularly with respect to the key ideas. Also, students are rarely asked to clarify, justify, or represent their beliefs, nor does the text make suggestions about when and how students will get feedback from their peers or their teacher.

The key physical science ideas examined here are not assessed adequately in the material. The material includes relevant items for only two of the ideas, but even these two ideas are not assessed sufficiently. Furthermore, some of the relevant assessment tasks are not likely to be comprehensible to students.

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 as well as a test for each unit. These components have been evaluated for chapters 5, 8, and 9 and for unit 3.

For the idea that all matter is made up of atoms and molecules (Idea a), a single question is asked. In the Chapter 9 Test, students are to complete the statement “The particles that make up all matter are called ____” (Assessment: Chapter and Unit Tests, p. 59).

The idea that increased temperature means greater molecular motion, so that most substances expand when heated (Idea d), is covered by a few questions in the Chapter 8 Test. For example, students are to complete the statement “As a sample of matter is heated, its particles ______” (Assessment: Chapter and Unit Tests, p. 54); they are asked to choose the appropriate phrase from among four options (“stop moving,” “move more slowly,” “move more quickly,” and “are unaffected”). In another text, they are shown an illustration of a balloon with black dots on it, presumably representing air particles, and are asked to explain what will happen to the volume of the balloon if the temperature is lowered (Assessment: Chapter and Unit Tests, p. 55). Unfortunately, while this question is valid for the key idea, the illustration is likely to be incomprehensible. It is not clear whether the air particles are outside or inside the balloon, so students might not understand what they are required to do. The same illustration is shown to students in an additional test, in which they are asked to draw the balloon and to show how the position of the particles will change if the balloon is heated and the pressure is kept constant (Assessment: Chapter and Unit Tests, p. 56).

A few questions in the Chapter 8 Test pertain to ideas about the arrangement and motion of molecules in solids, liquids, and gases. The above two questions involving the balloon illustration focus on the idea that particles in gases spread evenly through the spaces they occupy. In addition, students are to choose the words or phrases that best complete the following statements:

Matter in which particles are arranged in repeating geometric patterns is a ______.

Matter in which the particles are free to move in all directions until they have spread evenly throughout their container is a ______.

The particles that make up a solid move _____ than do the particles that make up a gas.
[Assessment: Chapter and Unit Tests, pp. 53–54]

Students are to complete a table indicating whether particles are “close together” or “spread apart” in each state of matter. They are shown an illustration of a container with a supposed solid inside and are asked to draw the particles after the solid melts. Again, the illustration can be misleading to students, suggesting that the particles are in the solid (Assessment: Chapter and Unit Tests, pp. 55-56).

The teacher’s notes do not include suggestions of how to probe beyond students’ initial responses or how to modify instruction according to students’ responses. On the other hand, some questions are included that can help a well-informed teacher diagnose students’ difficulties with respect to some of the ideas examined. (Some of the relevant questions can be answered by copying from the text or by providing definitions for terms; hence, they are not described below.)

Students are to compare the characteristics of solids and liquids; explain (in terms of particle motion) why copper shrinks when it cools; and make charts to classify materials as solids, liquids, or gases, describing the particles in each state (p. 220st). Then, the teacher selects objects in the classroom and asks students to describe the particles and their movements within the selected objects (p. 220t). Students are to use the kinetic molecular theory to explain melting (p. 227s), the caving-in of an empty soda bottle in the freezer, the smell of ammonia from a leaking bottle, and warnings on cylinders of compressed gases about the highest temperature to which the cylinder may be exposed (p. 231s). They are asked to explain why the statement, “This room is full of air,” is incorrect and why liquid water forms on the outside of a glass of cold lemonade (p. 242s). They are told that alcohol evaporates more quickly than water and are asked what they can tell about the forces between the alcohol particles (p. 242s). Finally, they are asked to make a cycle map to show the changes in particles as cool water boils, changes to steam, and then changes back to cool water (p. 243s).

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, “Student results should be consistent with those of other groups” [p. 233t, item 1]), emphasize a “right-answer” approach (for example, “Check graphs for straight line fit” [p. 233t, item 3]), or use technical terms (for example, “…[T]he tea cools because its particles now have a lower average kinetic energy” [p. 242t, item 13]).

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., “Arons, A.B. A Guide to Introductory Physics Teaching. New York: John Wiley and Sons, 1990” [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. 232–233t).

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. 225st, MiniLAB Analysis, item 3; Critical Thinking/Problem Solving resource book, p. 15, item 1).

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. 4–31st). However, 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., p. 216t, Activity; pp. 232–233st, Activity 8–2; 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, at the end of Chapter 8: Solids, Liquids, and Gases, there is a People and Science section about Debra Moore, an African American glass artist. She answers questions about the scientific principles involved in her work, teaching her craft to children, and her personal interest in glass (p. 240st). In addition, Cultural Diversity teacher’s notes highlight specific cultural contributions related to chapter topics (e.g., pp. 237–238t). 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. 19–20). 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. 213s, Explore Activity), cooperative group activities (e.g., p. 226t, Reteach), laboratory investigations (e.g., p. 225st, MiniLAB), whole class discussions (e.g., p. 224t, Tying to Previous Knowledge), essay questions (e.g., p. 220st, Section Wrap-up Review), and concept mapping (e.g., p. 243st, item 23). In addition, multiple formats are suggested for assessment, including oral discussion (e.g., p. 220t, Assessment), essay (e.g., Assessment: Chapter and Unit Tests, p. 55), performance (e.g., Performance Assessment resource book, p. 23T, Skill Assessment 8), and portfolio (e.g., p. 241t, 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. 212t, Learning Styles). Several of the visual-spatial activities are also coded LEP for students with limited English proficiency (e.g., p. 251t, Activity 9–1). 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.

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 experiences students may have had that relate to the presented scientific concepts (e.g., p. 213s). In addition, some tasks ask students about particular personal experiences they may have had or suggest specific experiences they could have. For example, a portfolio assessment asks students to list examples of gases, liquids, and solids from home or school (p. 221t). 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. 224t, Tying to Previous Knowledge). Overall, support is brief and localized.