It is a newer concept, and is replacing many of the TC programs at
residential/day schools for the deaf. I don't know of any self contained public school programs that can be called bi-bi, usually for the reasons that Interpretator has already cited: lack of fluent ASL signing staff.
Ther problem that Interpretator cited for bi-bi approaches is true.....some children coming into the program have langauge delays becuase they have not been in an environment that allows for acquisition of either ASL or sufficient Englsih. However, this problem can be remediated through the use of early intervention programs that utilize a bi-bi approach and employ native or near native signers. As well, a preschool that utilizes a bi-bi approach will reinforce that which begins in the early intervention program. Inthat way, even a deaf child of a hearing parent is exposed to native or near native signers, and is allowed to acquire their L1 languge naturally despite the parents' less than fluent use of ASL. Parents who have made a committment to this apporoach can improve their signing skills along with the child's developing need for more sophisticated langauage. The exposure to native signers in an early intervention and preschool program will help to fill the gaps while the parent is developing fluency.
