I moved From St. Louis, Missouri to middle Tennessee when I was 6 years old. By the time I got to third grade, I had the accent down, and I wasn't yet used to people being dumb "down here".
It seems like we were supposed to be writing a story about a lion, and I asked the teacher how to spell "ferocious" . I thought I had it right, but I was going to ask her just to make sure. But when I asked her, she just looked at me. She said, "furious?" I said, "No, ferocious." She looked at me. I can't remember what else she said, but it left me with the impression that I'd dreamed it up and there was no such word.
Now. I have come up with a few questions pertaining to why she did this:

1. Did she purposely withhold this information from me because of her job? Did the school district and teachers' teachers tell them not to give children too much knowledge for fear that if they did, there would be practically no population in the south because everyone will have been smart enough to move away?

2. Was she formerly native to another culture which spoke a different language, and she was not familiar with this word, but was too embarrassed to admit this to a student?

3. Did she just not know how to spell it?

I have concluded that the third question is most likely to be the correct one.