This study investigated students' use of assistive technology (AT) tools within the context of Plan, Organize, Write, Edit, Revise (POWER) strategy instruction for writing explanations. Instruction took place in a fifth-grade classroom that included four students with learning, attention, or emotional disabilities and 19 peers without disabilities. The purpose of this study was to evaluate instructional effects and method of transcription used in composing science-related explanations. To examine effects of POWER instruction on writing quality and accuracy, researchers used a multiple baseline design across participants. Method of transcription was evaluated through a concurrent time series design. After POWER strategy instruction, participants' explanations earned quality and accuracy scores that were greater than their respective baseline scores. Scores on AT-transcribed responses exceeded those earned on handwritten explanations, with larger effects on accuracy than on quality. Implications are discussed in relation to POWER strategy instruction for students with disabilities who require transcription support.