| For many children with developmental disabilities, the everyday experiences of an inclusive preschool classroom are not enough to foster the adequate development of a tact repertoire, which consists of all the responses (tacts) that a speaker could emit in order to label environmental stimuli. The present study evaluated the effectiveness of using discrete-trial based embedded instruction for increasing the tact repertoires of four preschoolers with developmental delays and expressive language deficits. All four participants acquired tacts for common classroom items following the implementation of embedded instruction by teaching assistants. Students demonstrated acquired tacts to variable degrees during post-intervention probes. Based on student performances on probes, better learning outcomes resulted from embedding instruction into "planning" and "recall" times (small group instructional activities) than during the "worktime" (free play) period. Average percent correct on 1 wk post-intervention probes was 98% for planning items, 86% for recall items, and 63% for worktime items. Students obtained few, if any, of the control items that were not exposed to the intervention. Following training (task clarification, video modeling and criterion-based role-play), teaching assistants implemented instructional procedures with a high degree of fidelity (assistants averaged 94% correct implementation). Assistants later reported that they felt the instructional procedures were effective, easy to implement, and beneficial for this population of students. The results obtained have implications for early skill assessment, instructional design of preschool curriculums, and the professional development of educators. |
