Here are several groups that were working with in Haiti to help deaf children before the quake struck.
Institut Montfort is a school for deaf students in the capital city of Port-au-Prince.
Northwest Haiti Christian Mission runs a deaf school in Haiti.
A Catholic group, Reiser Relief was working this fall on establishing the Maranatha Orphanage for Children which includes deaf children (though that is not their focus).
The Children's Medical Mission of Haiti is associated with the Episcopal church and had some outreach to the deaf there before the quake.
