Fenner taught at several Victorian schools before being appointed (joint?) principal of the
Ballarat School of Mines in November 1914. He also had charge of the school's Geology department, the teaching of which was favorably commented on by examiners. He paid particular attention to
field work, which the students enjoyed, as well as being important to their education. Fenner also prepared students for the Geology examinations at
Melbourne University, with notable success. In 1916 he accepted the post of Superintendent of Technical Education in South Australia, a position he held until May 1939, when he was appointed acting
Director of Education in place of
W. J. Adey who was on the eve of retirement. During that time he completed research work for his D.Sc and from 1929 He worked as a volunteer for the
South Australian Museum, pursuing his research into
tektites, among other interests, and contributed numbers of articles to
Walkabout, until 1954 when he suffered a
stroke, and died a year later. His remains were buried in the
Centennial Park Cemetery. ==Other interests==