In this paper, we present how creation and dynamic synthesis of linguistic resources of Greek Sign Language (GSL) may serve to support development and provide content to an educational multitask platform for the teaching of GSL in early elementary school classes. The presented system utilizes standard virtual character (VC) animation technologies for the synthesis of sign sequences/streams, exploiting digital linguistic resources of both lexicon and grammar of GSL. Input to the system is written Greek text, which is transformed into GSL and animated on screen. To achieve this, a syntactic parser decodes the structural patterns of written Greek and matches them into equivalent patterns of GSL, which are then signed by a VC. The adopted notation system for the representation of GSL phonology incorporated in the system's lexical knowledge database, is Hamburg Notation System (HamNoSys). For the implementation of the virtual signer tool, the definition of the VC follows the h-anim standard and is implemented in a web browser using a standard VRML plug-in.