In the third article in a series on professional development, Sarah Garland writes about Tiferes Bnos, an all-girls school located on the first floor of an apartment building near the border of the Williamsburg and Bedford-Stuyvesant sections of Brooklyn. The vast majority of the school's 430 students, come from poor Yiddish speaking homes, yet for the past decade Principal Miriam Amsel, has coaxed excellence out of both students and teachers.