I attended (well, watched from an "overflow theater") a great presentation at ASHA Convention in Denver, Practical Strategies for Middle School and High School Language Learning Disorders (Wallach, Bartholomew & Charlton), that covered a number of strategies that can be practiced in the context of expository (or narrative) text:
-Recognizing and interpreting subordinate clauses
-Sentence Combining (see the work and resources of Killagon)
-Teaching Self-Monitoring and Metacognition (I've recently been putting the TWA Strategy on a Bookmark for students:
-Within the above, supporting comprehension and expression (summarizing) is analysis of text structure and use of graphic organizers; Mindwing's Thememaker® and the Thinking Maps programs are both approaches to understanding expository text structure.
So, where to get the contexts? I recently discovered ReadWorks- this website provides free access to reading passages and much more, with skill and strategy units on many topics in comprehension. The passages are searchable or organized by various categories--they are also Lexile-leveled. The website recently released a collection geared toward expository text structures as mentioned above.
Check out Readworks and sign up for a free account. The website is iPad-friendly, so you can activate Speak Screen while using a passage to have it read aloud, or download and "Open In..." an app such as Adobe Acrobat Reader in order to use highlighting and other annotation tools.