Signing systems that attempted to represent spoken language via manual signs -- some invented, and some borrowed from natural sign languages -- have historically been used in classrooms with deaf children. However, despite decades of research and use of these systems in the classroom, there is little evidence supporting their educational…

This article explores the available research literature on language development and language interventions among deaf and hard of hearing (d/hh) children. This literature is divided into two broad categories: Research on natural languages (specifically American Sign Language and spoken English) and research on communication systems (specifically…