Abstract
The main aim of the present field study is to present an intervention of teaching grammatical structures of the GSL with explicit instruction to Deaf and Hard of Hearing -DHH- pre- school and early school pupils. According to theoretical and field research findings, exposing children early to GSL, proper teaching tools, gradual maturation of the language and corresponding developmental milestones of DHH are achieved . The knowledge of a visual, accessible language, such as GSL, is directly related to the degree of knowledge and understanding of written language by deaf children and consequently their literacy. In bilingual education, GSL is the first and dominant language that DHH students should learn in the same way hearing students learn spoken and written languages , aiming at language proficiency in the first language and the acquisition of meta-linguistic skills. GSL should not be used only as a communication medium but rather as a school subject teaching its linguistic and grammatical-syntactic structures. Teaching interventions were videotaped on a weekly basis so we can evaluate them and improve them when and where necessary. Assessments of students’ language skills were done by carefully observation of videos with students’ sign language productions that are included in each student’s portfolio. The aim is to find out whether the systematic teaching of grammatical structures contributes to the linguistic development of the GSL and furthermore the written and spoken language.