Abstract: A kit for the assembly of various electrical circuitry, particlarly for didactical purposes comprising a selection of electrical or electronics components. Each component is mounted on an insulated board having extentions of a conductive material to which the component's terminals are electrically connected. The boards are adapted to be interchangeably and releasably mounted on a base in the form of a prismatic block made of a rigid, electrical insulating material. Metallic sockets are installed within the blocks. Releasable fasteners, such as screws, are used for establishing electrical connection between each conductive extention and associated socket, and wire plugs are inserted into openings formed in the side surfaces of the block.