This study conducts an acquisition-based evaluation of four primary-school English textbook series used in China. The evaluation aims to determine whether the sequencing of grammatical structures in the series is compatible with the L2 learning sequence stipulated in Processability Theory (PT). The results show a partial agreement between the sequencing of structures as teaching objectives in the series and the PT-based processability hierarchy. The sequencing of structures in the initial stages is consistent with the learning sequence of L2 English stated in PT. However, several structures in the intermediate or high stages are taught in a deviant way against their sequencing in PT. The deviant grading of those structures is possibly associated with the theme-based guidelines adopted in the textbooks. It appears that concerns with the utility of grammatical structures in a given context take precedence over concerns for L2 development. A number of suggestions are offered to textbook writers in terms of the role of input, the learners, developmental readiness, and the issue of heterogeneity in L2 classrooms.
