Research has indicated that current information about reading and the effective teaching of reading has not yet made much impact on content area textbooks. As a result, there is much room for improvement in how textbooks are written. Recent research has yielded a great deal of information about what makes a text more understandable and supportive to the student in learning concepts. Yet research in the area of text adaptation indicates that the process of revision is complex and cannot be addressed with simple solutions. Publishers also need to consider particularly the need for inclusion of additional graphics and attention not only to the content but also to the organization and style of the text. (Sixteen references are attached.) (RS)