Fourteen collections of children's reading materials were used to investigate the claim that collections of authentic texts with a common theme, or written by one author, afford readers with more repeated exposures to new words than unrelated materials. The collections, distinguished by relative thematic tightness, authorship (1 vs. 4 authors), and register (narrative vs. expository), were analyzed to determine how often, and under what conditions, specialized vocabulary recycles within the materials. Findings indicated that thematic relationships impacted specialized vocabulary recycling within expository collections (primarily content words), whereas authorship impacted recycling within narrative collections (primarily names of characters, places, etc.). Theme-based expository collections also contained much higher percentages of theme-related words than their theme-based narrative counterparts. The findings were used to give nuance to the vocabulary-recycling claims of narrow reading and to more general theories and practices involving wide and extensive reading. (Contains 5 tables and 2 figures.)