Objective: The purpose of this investigation was to examine the effectiveness of the Expanding Expression Tool (EET) to improve overall vocabulary skills of school-age children diagnosed with expressive language impairment (LI) by targeting semantic features through this multi-modal approach. Method: Three second and third graders diagnosed with expressive LI and on an active Individualized Education Plan (IEP) participated in this AB single case design investigation. The primary dependent variable (PDV) was the number of semantic features produced to describe the Tier 1 vocabulary words. The secondary dependent variable (SDV) assessed was the number of semantic features each participant provided to describe grade-level high frequency vocabulary words. The independent variable (IV) was the EET, a multi-modal intervention tool that targets semantic language through explicit instruction of semantic features. Results: All five participants’ data showed an increase in the number of semantic features produced when measuring their performance for the PDV. Additionally, all participants exhibited increases when measuring their progress for the SDV. Conclusion: The results of this investigation support the use of The EET intervention program as an effective means to facilitate the depth and breadth of the vocabulary skills of school-age students diagnosed with LI. Future research is needed to provide further evidence that the skills acquired during intervention are retained over time.
