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Middle and High School Science Textbooks
A Standards-Based Evaluation

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Does the material provide multiple and varied phenomena to support the key ideas?

Explanation. Scientists construct and use scientific knowledge to describe, explain, predict, and design real-world objects, systems, or events. Therefore, scientific ideas need to be connected to pieces of the real world. The issue here is whether the material provides a sufficient number of real-world objects, systems, or events in a variety of contexts to make the key ideas plausible. These may be observed firsthand or indirectly, through the use of text or videos or pictures.

Curriculum materials need to provide experiences with phenomena whether the key ideas describe a general phenomenon or an abstract idea. If a key idea describes a general phenomenon (e.g., "Water in an open container disappears"), addressing this criterion involves having students encounter instances of the general phenomenon (e.g., observing that the water level drops in a fish tank that is left uncovered). If a key idea describes an abstract idea (e.g., "Atoms and molecules are in perpetual motion"), addressing this criterion involves presenting students with phenomena that make the idea appear credible (e.g., students sitting closer to a newly opened bottle of perfume smell it sooner than students sitting further away).

The number of phenomena that are necessary to make the key idea plausible depends on the difficulty of the key idea and the level of generalization it requires. "Varied" means that materials should provide experiences in a variety of contexts: contexts within a particular scientific field (e.g., biology), contexts from different scientific fields (e.g., biology, chemistry, physics), contexts from different disciplines (e.g., mathematics, science, technology), or contexts from everyday experience. Providing experiences in a variety of contexts is important for most key ideas. It is particularly important for key ideas from Benchmarks chapters 1–3 (The Nature of Science, The Nature of Mathematics, and The Nature of Technology) and chapter 11 (Common Themes), since understanding the ideas in these benchmarks requires encountering them and generalizing their applicability across several domains. For example, to support the idea that "Thinking about things as systems means looking for how every part relates to others," experiences need to be provided for a variety of systems from different scientific fields and disciplines, such as an ecosystem or solar system, an educational or monetary system, and a telephone or transportation system. But even for a relatively simple benchmark, such as "Water in an open container disappears," experiences with a variety of phenomena—such as the drying-out of unwrapped bread, the drying of clothes on a clothesline, the drying-up of paints, the monitoring of the water level of an uncovered fish tank, and the monitoring of the level of puddles on a sidewalk—will be helpful.

Indicators of meeting the criterion

  1. Phenomena are useful in making the key ideas real.
  2. Phenomena are explicitly linked to the relevant key ideas. [6],[7]

Rating Scheme
Excellent: The material provides a sufficient number and variety of phenomena that meet indicators 1 and 2.
Satisfactory: The material provides some phenomena that meet indicators 1 and 2.
Poor: The material provides, at best, one phenomenon that meets indicators 1 and 2.

If the benchmark for which the material is analyzed includes several ideas, the reviewers should proceed as follows:

  1. Identify the ideas for which there is a content match.
  2. Score the treatment of each idea that results from step a. The overall score for this criterion will be the average of the scores for each idea.


To see the text of an indicator, place your mouse cursor over the relevant indicator number. The explanation will appear on your screen.

Key to Chart Symbols
Example(s) meet(s) the indicator.
Example(s) do(es) not meet the indicator.
Example(s) partially meet(s) the indicator.
  Not used to illustrate the indicator.
Physical Science
Examples from
  Matter and Molecules

  Chemistry That Applies


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