A study examined whether teaching a specific reading strategy could improve the reading comprehension and memory of young (18 to 32) and older (62 and older) high school educated adults with average to high vocabulary test scores. The "plan strategy" was identified through an examination of what more than 1,000 adults wrote down as they read and recalled magazine articles, which showed that successful readers of all ages appeared to search out and follow a text's subordinate relational structure and to focus on its message and its relationship to supporting major details. The subjects were stratified on vocabulary scores and randomly assigned to three groups, who (1) learned about five basic top-level structures (writing plans) used by authors to organize ideas and how to apply them to their reading, (2) practiced reading and remembering information, or (3) received no instruction. Results of pretesting and posttesting on recall and comprehension indicated that subjects in the strategy group learned to employ the plan strategy and to answer main idea questions correctly. They shifted in the types of information considered important and claimed improved reading strategies, superior memory for their reading, and increased interest in and enjoyment of reading. Both older and younger readers in the strategy group improved equivalently and maintained their improvement over time. (The paper contains descriptions of the five basic writing plans and signals that cue readers to them, a description of a young adult's performance and change in recall of problem/solution texts on pretest to posttest, a reading plan schematic, and copies of reading materials used in the study.) (FL)