In 1850 Frances Buss gained the Queen's College diploma for teaching. Inspired by her training, Buss decided to start her own school and later that year the North London Collegiate School for Girls was established. In an attempt to achieve and maintain high standards, Buss only employed qualified teachers. She also made use of visiting lecturers from Queen's College.

The North London Collegiate School soon developed a reputation for providing an excellent education for its students. In 1871 Frances Buss took the decision to change her North London Collegiate School from a private school to an endowed grammar school. Although this resulted in a loss of income, Buss was now able to offer a good education for those girls whose families could not afford the fees of a private school.