Date of Award


Degree Name



College of Liberal Arts

Type of Degree


Document Type


First Advisor

Hyo-Chang Hong

Second Advisor

Jun Zhao

Third Advisor

Benjamin White


The purpose of this study is to investigate lexico-grammatical changes in the language of instruction in the Language Arts textbooks from four consecutive grades. The nature and rate of such changes are addressed within the framework of Systemic Functional Linguistics. The study focuses on analyzing lexical density and variation, grammatical intricacy, process types, and clause complexes in the sample texts obtained from four elementary school textbooks for 2nd, 3rd, 4th, and 5th grades. The analysis shows that there are gradual changes in the lexico-grammatical features of the language of instruction across the grade levels; however, these gradual changes are not proportional to the increase of the grade levels. The lower grade texts employ lexico-grammatical and logico-semantic patterns different from those of the higher grade texts. Furthermore, it is suggested that the lexico-grammatical disparity revealed in the data may be partially responsible for the “4th grade slump” commonly discussed among elementary school educators.


English language - Textbooks - Evaluation.