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Science 2000. Decision Development Corporation, 1991 and 1995

Physical Science

1.
About this Evaluation Report

2.
Content Analysis

3.
Instructional Analysis

	Categories
I.	Providing a Sense of Purpose [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.	Taking Account of Student Ideas [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.	Engaging Students with Relevant Phenomena [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.	Developing and Using Scientific Ideas [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.	Promoting Students' Thinking about Phenomena, Experiences, and Knowledge [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.	Assessing Progress [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.	Enhancing the Science Learning Environment [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.
	References

I. Providing a Sense of Purpose

Conveying unit purpose (Rating = Satisfactory)

Each unit in Science 2000 is developed around a general investigative question to be explored and answered during the course of the unit. A unit consists of between seven and nine clusters. Each cluster focuses on a more defined and specific aspect of the unit’s broad investigative question. An overview accompanies each unit. Each overview—written for students—includes a background section that identifies what students will learn in the unit, a story-line section that elaborates the story line of the unit and is aimed at capturing student’s attention and interest, and a listing of the investigative questions for the unit and its clusters, and for the lessons within the clusters.

Grade 7, unit 3 (on the physics of motion) is framed both through the narrative and the questions included in the background and story-line sections of the unit’s overview. In the background section, students are told that they will explore what causes motion. This issue is made both comprehensible and interesting to students by being related to experiences in their everyday lives. For example, students are told to suppose a friend was leaning up against a wall:

“Hey,” she shouted, “look at the wall pushing on me!” Until you have completed Unit 3 of Science 2000, you might think she was not quite herself that day. While investigating balanced and unbalanced forces, you will learn that walls can push us every bit as much as we push on them! [grade 7, Teacher’s Guide, p. 5.11]

The unit’s story line makes the unit purpose further interesting to students. They are told that, in the context of encouraging bicycling in their city, the city’s newly established Bicycle Advisory Board is sponsoring a citywide All-Terrain Bicycle Design Contest:

Preparation for this design contest remains the focus of much of this unit. Your class will be challenged to design bicycles that can travel over a variety of terrain, including ice, snow, water, sand, and even a lava field!

What are the factors involved in designing a bicycle that can move across different types of terrain? How does a bicycle move? How does it start and stop? How does a bicycle turn and why doesn’t it fall over? All of these questions investigate the physics of motion. [grade 7, Teacher’s Guide, p. 5.11]

The material does not provide explicit opportunities for students to think about and discuss the presented unit purpose.

The clusters within the unit are generally consistent with the purpose of designing bicycles that can travel over a variety of terrain. They focus on investigative questions, such as: “How fast does a bicycle move?” “How can a small bicycle tire support my weight?” “How does a bicycle start and stop?” and “How does the weight of a bicycle affect its motion?” (grade 7, Teacher’s Guide, pp. 5.11–12). Students, however, may not always see the link between the lessons and the unit purpose since it is not consistently made explicit for them. The last cluster in the unit (cluster 25, and in particular, lesson 3, which is described as being “the culminating evaluation for the entire unit”) returns to the unit purpose, namely, the design of an all-terrain bicycle. The individual student reports and small group presentations that result from this final lesson are to incorporate explanations of how the motions and features of the students’ bicycles work “in terms of the physics of motion” (7.3.25.3, LP25, p. 10).

The clusters within the unit are framed through the investigative questions listed above. The questions are likely to be comprehensible but may not prove highly interesting for the majority of seventh-grade students (for example, “How does the weight of a bicycle affect its motion?”). On the other hand, the challenge or goal of designing an all-terrain bicycle—which extends across the entire unit—may provide ongoing motivation for the clusters’ activities. In most clusters, students are not given an opportunity to think about and discuss the investigative question of the cluster as they begin with the cluster activities (an exception is cluster 20). In some clusters, the lessons and the activities within lessons are consistent with the cluster purpose (i.e., the investigative question), but in others they are not. The material does not return to the stated cluster purpose at the end of the cluster.

Conveying lesson/activity purpose (Rating = Fair)

The material is inconsistent in conveying the lesson and activity purposes. Only in some instances does it convey the purpose of lessons and individual activities within lessons to students. One or more investigative questions serve as the title for each lesson (for example, “What is a gas? What is air pressure? How can we increase the inside pressure of an enclosed gas?” [7.3.20.1], and “How does temperature affect an enclosed gas?” [7.3.20.3]). The investigative questions are listed both in the unit and cluster overviews, which are available to students. However, it is not clear whether the material expects teachers consistently to share these questions with their students and identify them as purposes for the lessons. Investigative questions are often likely to be comprehensible to students (for example, “How can we determine the speed of a moving bicycle?” [7.3.19.3], “How does temperature affect an enclosed gas?” [7.3.20.3], and “What does it take to start an object in motion?” [7.3.21.1]), but sometimes they use terms or abstractions that are not likely to make sense to students who have not studied the lesson (e.g., “What is a gas? What is air pressure? How can we increase the inside pressure of an enclosed gas?” [7.3.20.1], and “How is impulse related to bicycles and their motion?” [7.3.22.2]). Students sometimes have a chance to discuss the investigative questions. In other cases, they are asked questions that set the stage for a lesson’s activities but the questions are not explicitly about the purpose identified in the investigative questions. At a finer grain size, the material sometimes conveys or asks teachers to convey the purpose of activities (such as demonstrations and student investigations) to students, while at other times it does not. In most cases in which a purpose is conveyed to students, they would be likely to tell “what” they are doing, but probably not “why.” The material rarely connects the purposes of individual lessons and activities to the purpose of the unit.

Justifying lesson/activity sequence (Rating = Satisfactory)

The unit and cluster story lines and the cluster investigative questions provide an outline of the unit and clusters and string together the clusters and lessons within them in an interesting way. However, they do not provide an explicit or detailed rationale for why clusters within the unit and lessons within clusters are sequenced the way they are. A rationale for the sequence of the activities within most lessons can be readily inferred from the lesson preview provided in each lesson plan.

II. Taking Account of Student Ideas

Attending to prerequisite knowledge and skills (Rating = Poor)

The only indication that there may be prerequisite knowledge or skills needed to learn the key physical science ideas in any of the Science 2000 lessons is the occasional prompt for the teacher to review or remind students of prior learnings. The material addresses a few prerequisite ideas, such as the idea that materials can exist in different states—solid, liquid, and gas—and that some common materials, such as water, can be changed from one state to another by heating or cooling. In grade 5, for example, lesson 1 of cluster 1 reviews the three states of water and lesson 2 notes that “[a]s heat is added or taken from water, the water can change states from solid, to liquid, to gas” (5.1.1.2, LP2, p. 17). However, the material does not alert teachers, nor does it address other important prerequisites, to understanding the kinetic molecular theory, such as that gases are matter. Also noteworthy is the extensive use of the term “molecules” by the series in the fifth-grade materials before devoting time to establishing what atoms and molecules are in the sixth-grade materials.

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

The material does not describe for the teacher’s benefit any of the commonly held ideas related to the kinetic molecular theory that have been documented in research studies. For example, research on student understanding of the structure of matter reveals that many students think that particles (atoms or molecules) are in substances and/or that there is something (e.g., air) between the particles, rather than that particles are substances consisting of nothing except molecules with empty spaces between them (Brook, Briggs, & Driver, 1984; Nussbaum, 1985; Lee, Eichinger, Anderson, Berkheimer, & Blakeslee, 1993). Research also reveals that students often confuse observable properties of substances and properties of molecules themselves. For example, students may think that molecules themselves become hot or cold, or that molecules themselves expand and cause substances to expand (Johnston & Driver, 1989; Lee et al., 1993).

Not only does Science 2000 not alert teachers to the numerous commonly held student misconceptions documented in research studies, but it occasionally presents material in ways that are likely to reinforce (at least some) student misconceptions. For example, molecules or atoms are referred to as being “in” a substance rather than that they constitute the substance—that is, the substance is composed (solely) of molecules and/or atoms.

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

The material advises the teacher to “preassess” students’ thinking regarding particular ideas or topics (grades 5, 6, and 8, Teacher’s Guide, p. 8.1; grade 7, Teacher’s Guide, p. 1.9), and occasionally includes questions or other activities for this purpose. However, this does not occur consistently across each of the grades in the series. At times, the teacher’s notes simply prompt the teacher to preassess students’ understandings of an idea (e.g., “atomic theory” in 6.3.21.1, LP1, p. 5, preview 7), but they do not provide any indication either of what such an understanding might entail or of how to go about doing such a preassessment. The best examples of Science 2000 meeting this criterion come from lessons 1, 2, and 3 in grade 7, unit 3, cluster 20. Still, the number and variety of questions included in these lessons is not sufficient to elicit the numerous misconceptions and identify the various areas of difficulty that, as indicated in research studies, students have with the key ideas.

Addressing commonly held ideas (Rating = Poor)

Not only does Science 2000 not do this, but, as noted above under “Alerting teacher to commonly held student ideas,” it occasionally presents material in ways that are likely to reinforce (at least some) documented student misconceptions.

III. Engaging Students with Relevant Phenomena

Providing variety of phenomena (Rating = Poor)

Overall, the number and variety of phenomena that the material provide to support the key ideas are not adequate. There is a clear focus on phenomena that relate to gases, fewer phenomena that relate to liquids, and hardly any that relate to solids. Some phenomena are included that relate to the idea that particles in gases are moving (Idea c), and several phenomena support the idea that increased temperature means greater molecular motion (part of Idea d). However, no phenomena are presented on the expansion of solids or liquids (part of Idea d), and some important activities that relate to this idea (such as how temperature affects the solubility of gases in liquids, the dissolving of sugar in water, the viscosity of syrup or honey, or the rate of diffusion of tea in water) are optional. With regard to the different arrangement and motion of particles of solids, liquids, and gases (Idea e), students compare the compressibility of air and water in a syringe. In addition, the speed of sound in different media is related to the different proximity of molecules in solids, liquids and gases, but no specific examples of media are discussed in this context. The sixth-grade glossary entry for “diffusion” includes a generalization on how the rate of diffusion in solids, liquids, and gases relates to the different motion of their particles, but still does not include examples of specific solids and liquids, although it mentions air in the context of gases (6.4.27). Examples of changes of state are distributed through the material, but are never systematically linked to molecular explanations in terms of the arrangement, motion, and interactions between particles (Idea f). No phenomena are included that relate to the ideas that matter is made of atoms and molecules (Idea a) and that atoms and molecules are extremely small (Idea b).

Providing vivid experiences (Rating = Fair)

Some important phenomena (such as diffusion of food coloring in water at different temperatures and the different compressibility of air and water when pressed in a syringe), are presented to students in hands-on activities. Other phenomena are briefly described in the glossary (such as the diffusion of perfume), or are briefly mentioned in the teacher’s notes (such as water vapor being less dense than liquid water); however, it is unlikely that students will be able to form a mental picture of these phenomena. The experiences that support the key physical science ideas are sometimes repetitive. For example, in demonstrating that molecular motion increases when temperature increases, the fifth-grade and sixth-grade materials both involve the same phenomenon (food coloring diffusing at different rates in cold and hot water) (5.1.1.2 and 6.4.28.1). Also, the seventh-grade materials present the phenomenon that the circumference of a balloon changes with temperature both in a hands-on activity and through a video clip (7.3.20.3). Such replication (as opposed to using some other phenomenon) does not appear to be instructionally efficient.

IV. Developing and Using Scientific Ideas

Introducing terms meaningfully (Rating = Fair)

Science 2000 introduces terms in different parts and sections of the program. Student investigation sheets (which are included in the software) include certain terms as “hot buttons” that link to definitions of the terms in the glossary. So, presumably, if students view these sheets on the computer, they will explore the links. Lesson plans (which are also included in the software) sometimes include instructions to teachers about students looking up specific terms in the glossary. Lesson plans include, in the procedure section, additional terms linked to the glossary. However, it is not clear whether students are able to view the lesson plans or, if not, whether and how the teacher is to introduce these additional terms to them. Given these ambiguities, it is not always feasible to evaluate whether certain terms will or will not be introduced in the context of relevant experiences.

Regarding the terms for which it is clear how they are to be introduced, some are explored within the context of a first-hand experience. In these cases, the term is usually introduced prior to the experience rather than having the need for the term grow out of the experience. For example, in grade 5, when the term “state of water” is introduced (5.1.1.2, LP1, procedures 1, 2), students first brainstorm what is meant by “state of water,” and then point to different pictures and ask what state the water is in. Other terms are not linked well to a relevant experience. For example, in grade 6, cluster 21, lesson 1, the terms “matter,” “atoms,” and “molecules” are not introduced in the context of relevant experiences.

With respect to the number of terms introduced, in teaching the kinetic molecular theory, the material typically reduces the number of terms to those necessary for communication. In the context of introducing the atomic theory in grade 6, though, the material introduces (and links to the glossary) 12 mostly new terms on one page (“matter,” “atoms,” “microscopes,” “elements,” “protons,” “neutrons,” “nucleus,” “electrons,” “compounds,” “molecules,” “forces,” and “bonds”), some of which relate to content inappropriate for middle school students (6.3.21.1, SI21–1–B, p. 3). This may distract student understanding of the main idea the material is trying to communicate, that “all matter is composed of small building blocks called atoms” (6.3.21.1, LP1, p. 4).

Representing ideas effectively (Rating = Poor)

Very few of the representations included in Science 2000 are likely to make the key physical science ideas intelligible to students. One useful example is an analogy that may help to describe the size of atoms (Idea b). “If we could greatly enlarge that drop of water, making it as big as the earth, each water molecule would only be as large as an apple or orange” illustrates effectively how extremely small molecules are (6.4.25, glossary entry for “molecule”). However, most representations are either misleading or inaccurate, or the relevant features of the representation are not explicitly linked to what they represent. For example, in grade 6, cluster 28, lesson 1, a video animation (with minimal text and no audio) shows molecules (and atoms within) of water initially linked and rigid/fixed as ice, vibrating but still locked in position as liquid water when heat is added, and then separating and all leaving the open-top container as a gas when additional heat is added. This animation is inaccurate in that the molecules should vibrate as a solid (not be still), slide past one another as a liquid, and move significantly faster as a gas. In addition, when liquid water is heated, all molecules do not leave the container simultaneously. Most representations of the motion of molecules in the three states show molecules of solids still (see, for example, 5.1.1.2, LP1.2, procedure 7; 7.3.20.3, laser video clip: Behavior of Molecules in Solids, Liquids, and Gases; 8.3.15.2, laser video clip: Sound Transmission in Different Media).

Demonstrating use of knowledge (Rating = Poor)

The glossary occasionally presents as part of a definition an explanation of a type of phenomenon (such as “evaporation”), but does not relate it to the explanation of a specific phenomenon (such as “evaporation of water from an open jar left on the kitchen counter”), hence it does not demonstrate the use of knowledge (see, for example, 6.4.27, glossary entry for “evaporation”). In the lesson plans, teachers are occasionally instructed to ask students to explain specific phenomena. Brief explanations of these phenomena are typically included in the lesson plans. However, since the material does not instruct the teacher to use the answers to demonstrate the use of knowledge, such responses do not count as instances of demonstrating use of knowledge. Only rarely does the material explicitly suggest to teachers to give a specific explanation to students (for example, in grade 7, cluster 20, lesson 1, the teacher is instructed to explain to students why a less inflated ball has more “spring” than a more inflated ball, using the kinetic molecular theory [7.3.20.1, LP1, p. 3]).

Providing practice (Rating = Poor)

Overall, the number and variety of opportunities that the material provide for students to practice using the key ideas are not adequate. There are no opportunities for students to practice using the ideas that all matter is made of particles (Idea a) and that particles are extremely small (Idea b). There are a few opportunities for them to practice the idea that the molecules of a gas are far apart, while the molecules of a liquid are closer together (part of Idea e) and that particles in gases are constantly moving (Idea c) (for example, 7.3.20.2, LP2, p. 7, procedure 1: “How does air inside our bicycle tires help to support our weight?” “Describe what the molecules are doing in an inflated tire to give it greater “spring” than a flat tire”). There are some opportunities for students to practice the idea that increased temperature means increased molecular motion (Idea d) (for example, 7.3.20.4, LP4, p. 18, procedure 1: “What difference would you notice if you checked the pressure of your bicycle tires before a race and then after a long fast ride? Why?”), especially if teachers carry out the optional investigations in grade 6, unit 4, cluster 28, lesson 1. Many of the questions that could provide practice for students appear in the beginning of lesson plans in the context of review of previous lessons. Since it is likely that these questions will be answered in a class discussion (rather than individually), this would be practice for only a small portion of the students.

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

Encouraging students to explain their ideas (Rating = Satisfactory)

The teacher’s notes in Science 2000 lesson plans routinely instruct teachers to prompt students to express their ideas either in whole group discussions or in writing. In addition, Science 2000 encourages students directly to express their ideas by providing appropriately designed work sheets for each investigation (see, for example, grade 7, lesson plans, cluster 20, lessons 1, 3). Students are sometimes asked to justify or represent their ideas. A common pattern with student investigations is that students make predictions and then are asked to justify them (see, for example, 7.3.20.3, SI20–3b). After students express their ideas, teachers are typically asked to lead a class discussion in which the scientific ideas are developed. This way, some students may get feedback on the adequacy of their ideas. However, the material does not provide teachers with suggestions on how to diagnose student errors, explanations about how these errors may be corrected, or how to further develop students’ ideas. Such information would help teachers provide more useful feedback to each student.

Guiding student interpretation and reasoning (Rating = Fair)

Science 2000 includes specific questions to guide students’ thinking about most investigations. Such questions appear in the work sheets of the investigations and/or in the lesson plans to guide teachers in leading class discussions. Typically, the number and the sequence of the questions included are not adequate to gradually lead the students from one insight to another (see, for example, 6.4.28.1, SI28–1–A; 7.3.20.3, SI20–3c; as well as 7.3.20.3, LP3, procedure 4). Science 2000 rarely includes questions to guide students' thinking about what they read in the glossary or what they view in the video clips. This is an important drawback, since a lot of the information that relates to the key ideas is presented in these features of the program.

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

In the beginning of many lessons, the material gives students an opportunity express their ideas with regard to a phenomenon that relates to a key concept of the lesson. At the end of the lesson, students are asked to revise their initial ideas about the phenomenon based on what they have learned (see, for example, grade 7, cluster 20, lessons 1–3). However, students are not explicitly asked to think about how and why their ideas have changed, nor which ideas they do or do not understand as a result of the lesson.

VI. Assessing Progress

Aligning assessment to goals (Rating = Poor)

Science 2000 systematically includes cluster assessments. However, in most cases, they are not aimed at assessing the key physical science ideas—even in clusters where the ideas are extensively addressed. Most of the key physical science ideas are not assessed at all in Science 2000.

In grade 7, there are few items relevant to the idea that increased temperature means greater molecular motion, so most materials expand when heated (Idea d). In the cluster 20 assessments, students are to explain why a raft full of air that was left in the sun pops, and why a heated empty can that was capped and cooled then caved in. (While additional ideas are needed to provide the desired explanations, they are all taught in the cluster.) In the cluster 26 assessments, in the context of weather, students are to explain why the liquid in a thermometer rises when the temperature warms and falls when the temperature cools, (question 2), and whether a cubic meter of warm air is heavier than a cubic meter of cold air (question 6). The weight question and the question “What is air pressure?” also assess the idea that, in gases, particles spread evenly through the spaces they occupy and move in all directions (part of Idea e).

Other than these questions, the material does not include questions that require the specific key physical science ideas.

Testing for understanding (Rating = Poor)

All of the relevant assessment items that are described under the previous criterion require understanding of the key physical science ideas, and some tasks are novel. However, only two of the key ideas are assessed in this manner.

Using assessment to inform instruction (Rating = Poor)

The professional development component of Science 2000 states that the strategy of informing instruction based on students’ performance is a powerful one, and it encourages the teacher to observe students to get informal feedback:

[F]ormative assessment offers guidance for improvement and is an ongoing process. It can be formal…or informal…. Because many students work independently or in groups during Science 2000 lessons, the teacher is able to circulate in the classroom, observe students, and get informal feedback…. During lessons, teachers are encouraged to informally assess students’ comprehension by observing their progress at the activities. [grade 6, p. 19.3]

In the Teacher’s Guide, however, there is no explicit mention of this instructional strategy and no specific reference to questions or tasks. Assessment is discussed in the Science 2000 Instructional Approach (pp. 8.1, 8.2), which states that the questions in step 1 are for preassessment and should be used to “guide the teacher in building bridges to new content” (p. 8.2), and that those in step 5 (Evaluation) are for the “final step in a constructivist learning sequence.” The paragraph notes that Science 2000 “outlines a variety of strategies for assessing the conceptual understanding achieved by students” and that “[t]here are structured assessment questions or assignments after many lessons and after each cluster.” It further notes that “many of these engage students in the applications of concepts and knowledge” (p. 8.2). However, the role of these assessments in instruction is not made explicit. Likewise, Chapter 13: The Science 2000 Software, includes a paragraph on assessments that notes that

Science 2000 includes short written tests of student understanding of each cluster.… Some of the assessments ask for quite specific information to check problem-solving and mathematical skills while others ask for more formative responses such as ideas the students had while conducting an investigation. [p. 13.8]

However, no mention is made of the function of the assessments in instruction.

Although not explicit, Science 2000 does include some opportunities for students to express and apply relevant ideas (see the above criteria entitled “Encouraging students to examine their ideas” and “Providing practice”) that can be used, in principle, by a well-informed teacher to diagnose students’ remaining difficulties. However, while some relevant questions are included, Science 2000 does not include suggestions for teachers about how to probe beyond students’ initial responses to better understand where they are, nor does it include specific suggestions 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. Teacher Background notes in the lesson plans usually provide sophisticated versions of ideas for each lesson. However, the advanced explanations often do not explicitly alert teachers to how ideas have been simplified for students (e.g., 6.4.28.1, LP1, p. 6, Background) and are sometimes brief (e.g., 6.3.21.1, LP1, p. 4, Background). Overall, the teacher content support may be used as a selective but not comprehensive content resource by the teacher.

The material provides some sufficiently detailed answers to questions in the student text for teachers to understand and interpret various student responses (e.g., 5.1.1.2, SI1–2–B, Teacher Answer Key, p. 9, item 4). However, there are some limitations to the responses provided in the teacher’s notes, which are sometimes brief and require further explanation (for example, “Water changes from a liquid to solid [ice] at this temperature,” 5.1.1.2, SI1–2–A, Teacher Answer Key, p. 6, Station 2, item 2) or are incomplete (for example, the answer to the first task but not the second one is provided [5.1.1.2, SI1–2–A, Teacher Answer Key, p. 6, Station 1, item 1]).

The material provides minimal support in recommending resources for improving the teacher’s understanding of key ideas. The material includes lists of mediagraphy (film, video, and software), teacher articles, teacher books, and organizations in the Resources component of each cluster. However, 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 general suggestions for how to encourage students’ questions and guide their search for answers. Introductory teacher’s notes in the Professional Development Teacher’s Guide state that “teachers can encourage students to develop their own questions and to conduct their own observations and experiments” (8.PD, p. 6.2). In addition, the teacher’s notes describing teacher lesson plans state that “lessons are designed so students have to ask questions and figure out how to find the answers” (8.PD, p. 7.1).

The material provides some suggestions for how to respect and value students’ ideas. Teacher’s notes state that multiple student answers should be acceptable for selected questions (e.g., 5.1.1.2, SI1–2–B, Teacher Answer Key, p. 9, item 1), and the student text explicitly elicits and values students’ own ideas in some hypothesis and design tasks (e.g., 7.3.20.2, LP2, p. 11, Procedure, item 9).

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?” But 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., 6.4.28.1, SI28–1–A, p. 1, items 1, 2; 26.4.28.2, SI28–2–B, p. 21, item [a]).

The material provides some suggestions for how to avoid dogmatism. Introductory teacher’s notes emphasize the role of the teacher as “a facilitator and a question-asker, encouraging students to articulate what they already know and to draw on their knowledge as they pursue an investigation” (8.PD, p. 6.2). The student text portrays the nature of science as a human enterprise in which students may participate (e.g., 6.4.28.1, SI28–1–A, pp. 1–3) and highlights the work of some current scientists in the Scientists in Action component (e.g., 5.1.1.Scientists in Action component, Clark, Eugenie).

The material provides a few examples of classroom interactions through brief vignettes in the Science 2000 Professional Development Teacher’s Guide that illustrate appropriate ways to respond to student questions or ideas (e.g., 8.PD, pp. 1.1–1.2). In addition, a limited sense of desirable student-student interactions may be gained from procedural directions for laboratories and cooperative group activities (e.g., 8.PD, pp. 19.6–19.10; 6.4.28.1, SI28–1–C, pp. 11–13; 7.3.20.3, SI20-3a, p. 520).

Supporting all students (Considerable support is provided.)

The material generally avoids stereotypes or language that might be offensive to a particular group. Video clips include a diverse cultural mix of adults and children (e.g., 6.3.21.Careers component, mason, masonry; 6.3.21.Assessments component, Assessment [21–1], Cluster 21 Assessment, Do-It-Yourself Playground; 6.4.28.Scientists in Action component, Boyle, Robert [1627–1691], chemist). In addition, the material’s use of narrative dialogues (e.g., 6.3.21LP, pp. 1, 2, Storyline) along with traditional expository text 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 women and minorities appear in the Scientists in Action component that lists the names of scientists who have worked in the subject area, with links to biographies (e.g., 8.3.22.Scientists in Action component, Curie, Marie [1867–1934]) sometimes including video, still photographs, and links to other databases. In addition, some Careers, Extension (e.g., 6.4.28.2, LP2, p. 16, Extensions, item 3) and Option (e.g., 7.3.20.1, LP1, p. 5, Procedure, item 8, Option) features highlight cultural contributions related to chapter topics. For example, an entry about masons describes how masonry was a profession throughout the world from early times, and provides video examples of fine masonry from various countries, including China, Egypt and Greece (6.3.21.Careers component, mason). The cultural contributions within these components are interesting and informative, but may not be seen by students as central to the material because they are often presented separate from the main lesson plans and student investigations.

The material suggests multiple formats for students to express their ideas during instruction, including individual investigations (e.g., 7.3.20.3, SI20–3c, p. 521), journal or log writing (e.g., 6.4.28.1, LP1, p. 8, Procedure, item 1), cooperative group activities (e.g., 7.3.20.3, LP3, p. 14, Procedure, item 3), laboratory investigations (e.g., 5.1.1.2, SI1–2–B, pp. 7–8), whole class discussions (e.g., 6.3.21.1, LP1, p. 7, Procedure, item 7), essay questions (e.g., 6.4.28.1, SI28–1–C, p. 13, Questions, item 2), creative writing (e.g., 5.1.1.2, LP1, p. 22, Extensions, item 3), visual projects (e.g., 6.3.21.1, LP1, p. 8, Extensions, item 2), and role play (e.g., 5.1.1.2, LP2, p. 21, Procedure, item 7, Option). In addition, multiple formats are suggested for assessment, including oral discussion (e.g., 7.3.20.3, LP3, p. 14, Procedure, item [3]), essay (e.g., 7.3.20.Assessments component, Assessment [20–1]: Cluster 20 Assessment, item 2), and performance (e.g., 6.4.28.Assessments component, Assessment [28–1]: Cluster 28 Assessment). However, the material does not usually provide a variety of alternatives for the same task, but often includes additional optional activities (e.g., 5.1.1.2, LP2, p. 20, Procedure, item 6, Option).

The material does not routinely include specific suggestions about how teachers can modify activities for students with special needs. However, the material suggests that Extension activities may be used in place of parts of the lesson if deemed by the teacher to be “more appropriate for the class’ ability, background or interests” (8.PD, p. 7.1) and are later designated as suitable for gifted and advanced students (8.PD, p. 7.3). In addition, the material suggests that teachers provide opportunities for students to explore the database individually (8.PD, p. 18.4). For Spanish speakers, background descriptions of lessons, story lines, key concepts, many database entries, many student investigations, and other materials are written in Spanish and English (8.PD, p. 7.3). For hearing impaired students, the audiotrack of the video clips has close-captioning. For visually impaired students, some text is written in large type. Teacher tips provide additional suggestions for supporting limited English proficiency and bilingual students (8.PD, pp. 19.5–19.6, Computer Instruction with Language Minority Students).

The material provides many strategies to validate students’ relevant personal and social experiences with scientific ideas. Many tasks ask students about particular personal experiences they may have had or suggest specific experiences they could have. For example, in a class discussion introducing a lesson on gases and air pressure, the teacher’s notes suggest asking students how their bicycle tires support their weight, then discuss air as a type of gas, and consider how tires would ride if filled with different substances (7.3.20.1, LP1, pp. 2, 3, Procedure, items 1, 2). 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., 5.1.1.2, LP2, p. 21, Extensions, item 2).

1.	About this Evaluation Report
2.	Content Analysis
3.	Instructional Analysis

Middle Grades Science Textbooks: A Benchmarks-Based Evaluation