I would not liken ordinary and typical in this context, not in their Norwegian forms "ordinær og typisk" anyway. "Ingen ordinær lærer" could mean she wasn't really a teacher, maybe she was an engineer and just a substitute/extra teacher for a project, meaning she was something different from a teacher but she was teaching at the time nonetheless. "Ingen typisk lærer" says she is a teacher, but different from the rest of the teachers.
"The woman was no ordinary teacher" was indeed accepted for me in English when presented with the Norwegian sentence. (Mar 2017)
(Which is not to say ordinary should or should not be accepted in all sentences as a translation of typisk, just that it felt appropriate for this particular sentence.)
For non-native-English speakers: The English forms ordinary and typical are fairly close in this sentence. Grydolva's excellent comments for "Ingen ordinær lærer" would more closely align with "She's not ordinarily a teacher."