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Middle Grades Science Textbooks: A Benchmarks-Based Evaluation

BSCS Middle School Science & Technology: Systems and Change, Level C. Kendall/Hunt Publishing Company, 1999
Earth Science Life Science Physical Science

Authors: BSCS Development Team, BSCS, Colorado Springs, Colorado
Publisher: Kendall/Hunt Publishing Company
Edition: 1999
Web Site:

About this Evaluation Report

The BSCS Middle School Science & Technology series is a science program that distributes physical, Earth, and life science topics across three middle grades textbooks arranged by level (grade) and organized in theme-based units.

The program has been evaluated in terms of how well its content matches each of three topic-specific sets of key science ideas, and how well it provides effective instructional material in terms of a set of universal criteria for the teaching of science ideas.

This report on BSCS Middle School Science & Technology assesses the program’s life science component. However, the program’s coverage of the key life science ideas is so limited that what follows is simply a summary of findings regarding content, with no more than brief comments on the topic of instructional support.

In the following summary, some page references to the evaluated materials include the suffix “s” or “t” to distinguish between the student text and the Teacher’s Edition, respectively. The key science ideas and the instructional analysis categories are presented and discussed under Project 2061 Analysis Procedure on the main menu.

The life science idea set focuses on the transformations of matter and energy in living systems, including organisms and ecosystems. In terms of a content match, BSCS Middle School Science & Technology connects with only one of the key ideas, and even then, with only part of it.

The key idea involved is that decomposers transform dead organisms into simpler substances, which other organisms can reuse (Idea c4). A partial match occurs for the ideas being addressed in a few places in Systems and Change (level C). In Chapter 12: Exploring Energy in Systems, for example, the Teacher’s Edition lists as an outcome that students should understand that “microorganisms break down [plant] material and in the process transfer some of the energy stored…into heat energy” (p. 274t, Outcomes and Indicators of Success). In the student text, students consider compost piles as an example of a system in which energy transformation occurs (pp. 274s–277s). They first read a scenario about heat produced inside a pile of grass clippings left outside for a week. Then they plan and carry out compost experiments in plastic bottles and graph the temperature changes. At the end of this activity, they are asked what role the microorganisms played in the composting system and what form the energy was in before it was released as heat.

Another key life science idea—that plants use the energy from the sun to make their own food (Idea d1)—appears in the suggested answers to the discussion questions, but is not taught in the material. In one such question, students are asked to consider what would happen to a tree, a shark, and a squirrel if sunlight were prevented from reaching the Earth’s surface, and to explain in what ways living things depend on the sun’s energy (pp. 283s–284s). In a second question, students are shown a picture of a seedling and a picture of a bear (among other pictures) and are asked to define a system relevant to each case and to explain the evidence for energy and for energy transformation (pp. 284s–285s).

The material does not treat any of the key life science ideas involving transfer or transformation of matter, nor the idea that the transformation of chemical energy into mechanical work or heat occurs in organisms other than microorganisms. At the beginning of chapter 12, the Teacher’s Edition lists several systems that students might consider in terms of energy transformation, including a potted plant and a can of food. However, the inclusion of living things as examples is optional (p. 271t).

Note: Although this material was not further analyzed for the quality of instructional support it provides, it is worth noting that its use of composting as an example of a system provides vivid experiences for students that could be used to help make the idea of energy transformation in living things plausible.