The word "exposition" comes from 2 Latin words, ex+ponere, literally to place in front of, or to lay out, to set out, as in a description, explanation or argument. The content area teacher has two major tasks in teaching comprehension and composition of expository texts:
1) teaching students to identify the important concepts
2) teaching students to understand their relationships
The realities of teaching expository writing and comprehension of expository texts are that textbooks generate a significant amount of the classroom instruction required for teaching these skills. We'll therefore turn our attention to understanding how textbooks are designed, and then explore strategies that teachers can use in combination with this information for executing the two tasks mentioned above.

UNDERSTANDING TEXTBOOK DESIGN
Unfortunately, the quality of writing found in many content area texts is considerably weak. It can be poorly organized, packed with facts, unfriendly, and lacking in concepts. The characteristics of texts that are more user-friendly and readily comprehensible are (a) structure, (b) coherence, and (c) audience appropriateness. We will examine each in turn:
(a) STRUCTURE
Structure refers to how the text is organized and the signals it gives in connection with such organization. Following are some of the general textual elements that contribute to good structure:
Titles, Headings, Subheadings, Sections,
Introductions, Summary Statements, Graphics, Signal Words (First, Second, Then, Therefore), General Format, Table of Contents.
Readers organize their recall of information or their information processing schemas according to either text structure or background knowledge. Since students in alternative settings typically do not have much background knowledge in many of the content areas they are studying, they need to rely on these text structure elements for identifying the concepts and information that are important as well as for understanding expository text. Attention to these elements of structure also helps students as they try to compose texts in the expository mode when doing report-writing, summarizing information, and engaging in other expository tasks.

(b) COHERENCE
Coherence refers to how well the ideas in the text "stick together." With coherent text, the relationships among concepts are pretty clear. Skillful use of connective words also help to produce coherent text. Students rely on models, analogies, empirical reasoning, and transparent discussion to aid in comprehension of exposition. For example, learning to recognize the essential elements of a paragraph in which these rhetorical devices reside as well as expository paragraph signal words and phrases can help in both writing and understanding exposition.

Essential Elements of the Expository Paragraph
(Adapted from Kate Kinsella)
The essential elements of a paragraph are the topic, main idea, topic sentence, and details. The topic is the idea about which the entire paragraph is written; it is the single unifying factor. The main idea reflects the author's primary purpose in writing. It is the most important thought which the author desires to communicate in the entire paragraph. It may be explicitly stated or inferred. The topic sentence is the sentence containing the main idea of the paragraph, which may be stated either at the beginning or end of the paragraph. The supporting details are subsumed under the main idea in a paragraph. They are the reasons, facts, and examples that explain the main idea. While the "bones" are the main idea as it were, the details are the "meat" on the bones.

Expository Paragraph Signal Words
(Adapted from Kate Kinsella)
Words that signal:
Definition---refers to, consists of, means, in other words, etc.
Examples--for example, for instance, such as, is like, including, etc.
Listing--also, another, moreover, furthermore, finally, in addition etc.
Sequential Listing--first, second, later, next, before, then, finally, following etc.
Analysis--consider, analyze, investigate, examine, this means etc.
Comparison--similarly, just like, in the same way, likewise, in comparison etc.
Contrast--on the other hand, however, whereas, but, yet, in contrast etc.
Cause-Effect Relationship--because, for, therefore, hence, as a result, thus etc.

(c) AUDIENCE APPROPRIATENESS
Audience Appropriateness refers to how well the textbook is suited to the reader's knowledge, reading and study skills. The inadequacy of readability level formula techniques drives expository text composition and selection, so that often texts that are rewritten to meet a pre-designated readability level lose their coherence and structural integrity in the process. Ironically, the process which aims to make complex text simpler, can actually have the opposite effect. Teachers should therefore screen texts carefully to ensure their design is sound before assigning reading to students.

STRATEGIES FOR TEACHING EXPOSITION
Aside from understanding how textbooks are designed, and using this knowledge to teach expository reading and writing skills, there are some "packaged" strategies that teachers can draw on for teaching expository reading and writing. They all include similar elements, and focus students' attention on the process of interacting and engaging with text to promote a deep understanding of the content contained therein, as well as increasing the level of students' comfort zone more generally when reading and writing in the expository mode. Five such strategies are presented here as an aid to both teachers and students:

1. The K-W-H-L chart (Ogle 1986) IS a matrix that provides a graphic organization for students to list what they know about a topic (K), what they want to learn (W), how the information will be learned (H), and then finally, what they learned (L). The information is categorized, mapped, and finally summarized.
2. The QTA or "question the author" strategy (Beck et al., 1997) is a powerful textbook reading strategy designed to encourage deep and authentic interaction with texts and discussion with classmates. It is based on the premise that authors of texts are fallible. The teacher poses queries about the text content at selected intervals, and the students respond, refine, and expand their answers through discussions.
3. The VRG or "visual reading guide" (Moore, Readence & Rickelman, 1988) introduces students to a passage by examining the accompanying charts, graphs, diagrams, maps, and illustrations in order to formulate predictions about information in a text. This activity helps students draw connections between information presented in graphic aids, the text, and their prior knowledge.
4. Transactional Strategies Instruction or TSI (Pressley & Woloshyn, 1995) requires students to predict upcoming events in the text--that is check whether predictions made were consistent with the text content, react to text --that is, relate ideas to prior knowledge, construct images, make inferences, slow down, read carefully, check back, clarify, generate questions, and finally, summarize information gleaned from the text.
5. Reciprocal Teaching (Brown & Palinscar, 1984) has many of the thematic elements that run throughout the preceding strategies. The process involves question generation, summarizing, clarifying, and predicting, all done by the students, and based on the text read.

Finally, in addition to understanding textbook design and incorporating into their teaching specific strategies for expository reading and writing, teachers could also help students develop good study skills, and apply the following techniques for successful adaptation of the textbooks they are assigned or choose to use:

TEXTBOOK ADAPTATIONS
(a) Select compatible reading materials that cover similar content, but have a lower estimated readability level.
(b) Provide an outline of the text that the students can complete as they read.
(c) Underline key points and use margin notes to highlight important information.
(d) Develop a question guide in which the reader is asked to answer several relevant questions that relate to key sections in the text.
(e) Tape record vital segments of text using #s 1-4 as a guide.