Last names starting with "O"
- Class of 1957 Gerald Oberndorfer
- Class of 1968 Mary Obeurneffeman
- Class of 1977 Cheri OGuin
- Class of 1977 Cheri OGuinn
- Class of 1979 Patricia OKeefe (formerly Schneider)
- Class of 1998 Katherine OMalley
- Christy Orlet
- Class of 1980 David Orlet
- Class of 1972 Mark Osland
- Class of 1971 John Ostermeier
- Class of 2002 Shawn Overmiller
Looking for Althoff Catholic High School alumni not listed? If so, check out Classmates.com® - hundreds of more ACHS alumni have posted their profiles.
About the Althoff Catholic High School Alumni Directory
If you attended Althoff Catholic High and want to be added to the alumni directory register now to add your name to the alumni list. While you are reminiscing about the times you spent in high school at Althoff Catholic High School, you should also check out alumni photos, yearbook listings and share any reunion info if possible.