This study investigated the extent to which the language base as described in the three strands of the Language Experience Approach Rationale is provided for in the first grade reading textbook teacher guides adopted by the state of Arizona. Language experiences in a random sample consisting of five pages from each of the 77 books included on the adopted list were collected and tabulated. Each activity was classified according to an evaluation instrument based on the 20 language experiences suggested by the Language Experience Approach Rationale. Major conclusions included: (1) activities providing for a language base in first grade reading textbook guides on the Arizona adopted list show differences in emphasis among the Phonological, Syntactic-Morphological, and Semantic structures of language; (2) the greatest emphasis in the adoption as a whole is on the Syntactical-Morphological structure of language; (3) secondary emphasis in the adoption as a whole is on the Semantic structure of language; (4) a considerably lower emphasis in the adoption as a whole is on the Phonological structure of language; and (5) the twenty language experiences suggested by the language experiences rationale differed in the provision made for them in the combined adopted materials. (Author/WR)