The Sisters of St. Joseph used the O'Reilly House as a school almost from the time they arrived in St. Augustine in 1866. In 1874, the Sisters officially opened the doors of St. Joseph Academy. While a separate school building was later built on the property adjacent to the Motherhouse (which has since been torn down), classes continued to be held in the O'Reilly House until 1956. St. Joseph Academy is now an accredited high school with a modern facility located a few miles from the O'Reilly House Museum. Elementary and middle school grades continue to be taught at the Cathedral Parish School, located half a block south of the O'Reilly House.
Displayed inside the room is any number of objects used by the Sisters to instruct the students of St. Augustine. Examples include a number of musical instruments including a violin, a small harp, a box of percussive instruments, and even a table with the piano keyboard printed on its surface to assist in teaching proper fingering. Beakers used in laboratory experiments and a working mechanical model of the solar system show that the sciences were part of the curriculum. Vocations were also taught in the O'Reilly House.
It is also very evident from this room that religious instruction was at the core of the students' education. In the northwest corner of the room is a statue of St. Anthony. Both simple and adorned crucifixes are prominently placed around the room along with two prie-dieu, formerly used in the Motherhouse chapel in the 19th century, which speaks volumes about the tireless work the Sisters have performed in almost a century and a half of service here in St. Augustine.