Hadassah Blocker grew up in Roxbury and Dorchester, Massachusetts, in an Orthodox family as the oldest of four children of European immigrant parents. Her father, an Orthodox rabbi, worked as a Hebrew school teacher, and principal. Her mother ran the household and ensured there were coins in her kitchen's row of pushkes dedicated to different charities. Hadassah was graduated from Hebrew High School, Hebrew College, and Radcliffe College. She worked as the Director of Camp Pembroke, a Jewish camp for girls in Pembroke, Massachusetts, for 32 years.
When Hadassah's father saw her interest, as an adult, in reading the Bible, he encouraged her to learn how to chant Torah and provided her with tapes from which to learn. Hadassah developed an immediate passion for chanting Torah and knew this was a gift to be shared with others. With the support of Rabbi Samuel Chiel, Hadassah became the first woman to chant the Haftorah at her synagogue, Temple Emanuel of Newton, at a Sisterhood Shabbat over forty years ago. With that beginning, Hadassah began training other women to take part in the Torah service. She taught her first formal adult Bat Mitzvah class in 1976, focused on Hebrew, synagogue skills, and the chanting of Torah and Haftorah, to a group of thirty adult women. Hundreds of students have followed.
Despite resistance from many at Temple Emanuel, Hadassah persisted in pushing for the acceptance of women's participation in the service, continuing to teach and to advance the empowerment of women in synagogue life. Hadassah encouraged women of all ages to get involved in synagogue life, and many became B'not Mitzvah as a result of her commitment to quality adult Jewish education. For most women in her classes, the Bat Mitzvah was only the beginning. Many have pursued further study at Hebrew College and Temple Emanuel.
Hadassah lived in Newton where she continued to share the gift of Torah until her death on October 23, 2008.