The first mentions of a manor in Niedernfels can be found around the year 988.
The castle was built in 1568 by its new owner Augustin von Aham auf Valley in its current form in the Renaissance style and named "Niedernfels" because of its low location. In 1639 Rennerus von Fossa acquired the castle, which changed hands many times in the following centuries. The approximately 20-meter-high square palace with the two octagonal towers was expanded to include a four-story extension in 1808.
In 1954, Schloss Niedernfels became the property of the convent of the "Sisters of the Visitation of Mary", who in 1955 opened an elementary school with boarding school. In 1972 the offer was expanded to include a day care center for boys and girls. In 1997 the Catholic Youth Welfare Organization of the Archdiocese of Munich and Freising e.V. took over the sponsorship of Schloss Niedernfels. In 1998, two socio-educational residential groups and a curative educational day care group were opened. In 2001 the castle building was renovated: New rooms for day care and school were created as well as a modern central kitchen. Energy-related renovation measures such as the installation of a wood chip heating system and thermal insulation glazing could also be implemented in this construction phase.
The educational offer was expanded in 2004 to include all-day care for grades 7 to 9.
At the beginning of the 2009/2010 school year, the Franz von Sales School moved into the new, modern and spacious school building.
In September 2011, integration places could be set up in the after-school care center for the first time. The youth welfare offices approved an additional therapy hour per week for children who are "mentally handicapped or threatened by mental disability". In September 2012, an agreement was concluded with the Upper Bavaria district, responsible for schoolchildren with physical or mental disabilities, so that these children can also be accompanied by specialist services.
At the same time, in cooperation with the Achental Realschule Marquartstein, a special day care group was set up for junior high school students. Due to the high number of registrations for this secondary school group, the number of places was doubled in the 2013-2014 school year.