| Cosier, Corrie | In Service Education Branch | A. Advisory Teacher II | 1970 |
| Cosney, Leslie | Kurramia VIII | Head Teacher | 1918 |
| Cossil, Carolyn | Tranby Primary School | Mi/T. | 1970 |
| Cossil, Carolyn | Tranby Primary School | Mistress (Teacher) | 1972 |
| Cossill, Carolyn | Tranby Primary School | Mistress (Teacher) | 1971 |
| Cossing, Kimball | Bunbury High School | Master (Teacher) | 1957 |
| Cossins, T. A. | Plympton Infants IV | Head Teacher | 1900 |
| Cossins, Tryphena A. | Plympton Infants IV | Head Teacher | 1901 |
| Cossins, Tryphena A. | Plympton Infants IV | Head Teacher | 1902 |
| Cossins, Tryphena A. | Plympton Infants IV | Head Teacher | 1903 |
| Cossins, Tryphena A. | Plympton Infants IV | Head Teacher | 1904 |
| Cossins, Tryphena A. | Plympton Infants IV | Head Teacher | 1905 |
| Cossins, Tryphena A. | Plympton Infants IV | Head Teacher | 1906 |
| Cossins, Tryphena A. | Plympton Infants IV | Head Teacher | 1907 |
| Cossins, Tryphena A. | Plympton Infants IV | H.T (on leave) | 1908 |
| Cosslett, Lorraine Fay | Eastern Goldfields Senior High School | Mistress (Teacher) | 1971 |
| Cosstick, Peter Laurence | Mount Barker Primary School I | Master (Teacher) | 1973 |
| Cosstick, Peter Laurence | Mount Barker Primary School IA | Master (Teacher) | 1975 |
| Cosstick, Peter Laurence | Onslow Primary School II | Master (Teacher) | 1976 |
| Cosstick, Peter Laurence | Onslow Primary School | Master (Teacher) | 1977 |
| Cosstick, Susan Elizabeth | Mount Barker Primary School I | Mistress (Teacher) | 1973 |
| Cosstick, Susan Elizabeth | Mount Barker Primary School IA | Mistress (Teacher) | 1975 |
| Cosstick, Susan Elizabeth | Onslow Primary School II | Mistress (Teacher) | 1976 |
| Cosstick, Susan Elizabeth | Onslow Primary School | Mistress (Teacher) | 1977 |
| Cosstick, Susan Elizabeth | Onslow Primary School | Mistress (Teacher) | 1978 |
| Costa, Luigi Peter | Governor Stirling Senior High School | Master (Teacher) | 1973 |
| Costa, Luigi Peter | Governor Stirling Senior High | Master (Teacher) | 1975 |
| Costa, Luigi Peter | Governor Stirling Senior High School | Master (Teacher) | 1976 |
| Costa, Luigi Peter | Governor Stirling Senior High | Master (Teacher) | 1977 |
| Costa, Luigi Peter | Governor Stirling Senior High School | Master (Teacher) | 1978 |
| Costa, Luigi Peter | Governor Stirling Senior High School | Senior Master/Mistress (Teacher) Science and Physical Science | 1979 |
| Costa, Luigi Peter | Governor Stirling Senior High School | Master (Teacher) | 1980 |
| Costanzo, Silvana | Tranby Primary School | Mistress (Teacher) | 1979 |
| Costanzo, Silvana | Tranby Primary School | Mistress (Teacher) | 1980 |
| Costella, Winifred | Maylands II | Assistant Teacher on Supply | 1944 |
| Costello, Allan James | Mount Lawley Senior High School | Mistress (Teacher) | 1978 |
| Costello, Anne Dorothy | Kalamunda High School | Mistress (Teacher) | 1971 |
| Costello, Anne Dorothy | Mirrabooka Senior High School | Mistress (Teacher) | 1972 |
| Costello, B Mrs | Donnybrook Junior High School | Clerical Assistant | 1965 |
| Costello, B. | Donnybrook Junior High School | Clerical Assistant 0.2 | 1967 |
| Costello, B. | Donneybrook Junior High School | Cl Asst | 1968 |
| Costello, B. | Donnybrook Junior High School | CL Asst | 1969 |
| Costello, B. | Donnybrook Junior High School | Clerical Assistant 2/5 | 1970 |
| Costello, B. Mrs | Donnybrook Junior High School | 1/5 | 1966 |
| Costello, Cherie Louise | Boyanup Primary School III | Mistress (Teacher) | 1975 |
| Costello, Cherie Louise | Cooinda Primary School IA | Mistress (Teacher) | 1976 |
| Costello, Cherie Louise | Cooinda Primary School | Mistress (Teacher) | 1977 |
| Costello, Cherie Louise | Cooinda Primary School | Mistress (Teacher) | 1978 |
| Costello, Cherie Louise | Unattached | Mistress (Teacher) | 1979 |
| Costello, Costello Olga Beryl | Museum Classes | Acting Education Officer | 1977 |
