In this case it seems very much like the decision of an individual teacher and not broad educational policy.
Every strategy for plagiarism detection is also going to have false positives.
The word "circumnavigate" is always used with Magellan - it may as well be his middle name. It's used in the first two sentences on Magellan's page at La Wik.
My guess is the teacher didn't know know the word, found out it was a real one, and found it emotionally satisfying to punish a child for assaulting his status by demonstrating his ignorance, however unintentionally.
Some people feel very threatened by "big words" they don't know, and see use of language as a status play.
Years ago, one guy at work, who I actually consider very sh...
New chapter!
This is a new thread to discuss Eliezer Yudkowsky’s Harry Potter and the Methods of Rationality and anything related to it. This thread is intended for discussing chapter 102.
There is a site dedicated to the story at hpmor.com, which is now the place to go to find the authors notes and all sorts of other goodies. AdeleneDawner has kept an archive of Author’s Notes. (This goes up to the notes for chapter 76, and is now not updating. The authors notes from chapter 77 onwards are on hpmor.com.)
Spoiler Warning: this thread is full of spoilers. With few exceptions, spoilers for MOR and canon are fair game to post, without warning or rot13. More specifically: