Hmm, I just read the night's batch of suggestions.
There was no book. If the information had been in a book we had available, nobody would have been surprised that I knew it. The book I mentioned was one I acquired more than a year after the incident, which I just looked up to check that the facts weren't all illusion.
At that age, the likeliest other source for the information would have been a weekly magazine I got called "Look and Learn". But the weird bit is that I had no thought at all of "oh, I know this, I saw it in Look and Learn." All the time I was spouting the information I was visualising the teacher telling us the previous lesson, convinced I was just repeating what he had said to us less than 24 hours previously.
Yes, the whole thing surprised the heck out of me. Uri Geller was plastered all over the news at some stage, but I've a feeling that was a couple of years later, and anyway, my only wonder on that one was "what's the trick he's using?" Never even contemplated otherwise. (Never really thought it was as simple as bending by force while operating misdirection either, but there you go!)
I've thought about it quite often, it's just something which has always been in the back of my mind as "unexplained". I've told the story quite often over the years, now and again, not obsessively or anything, but just as an odd anecdote. I never forgot it and never changed the story.
Yes, my first explanation was that Mr. Brodie really had told us the previous day, and I was the only one of the 30 or so people present who remembered, including him. But like I said, there were a lot of pathological swots in that class. They'd jump at the bell, but they'd listen right up till that moment. ALL of them? It just seemed so unlikely.
For many years I toyed only with possible explanations of how I might have imagined the day 1 events, possibly putting together the information from subconscious previous knowledge. But I couldn't get over the fact that my memory was entirely of Mr. Brodie telling the class the information. I'm the sort of person who remembers information by where it was encountered - I can usually tell where on a page I read a certain fact, and flip the book just looking at that PART of the pages till I find it. This one, no memory of books or pages or diagrams, just the teacher talking.
Only a couple of years ago, when I told the story to another group of friends, did someone suggest that day 2 might have been a dream. When I thought about it, that was impossible to refute. Mr. Brodie really did tell the class about the fly just as I remembered, but I dreamed the whole incident of being asked the question and being the only one who could answer.
This is certainly theoretically possible. It just seems odd that it never even occurred to me as a possibility until someone else suggested it, and it was completely unlike any dream I've ever had. Including the fact that I don't remember my dreams in detail, except that they don't make internal sense, and they often involve me being unprepared or late or in a terrible rush.
Never had another similar experience. It's not that uncommon to remember things differently from other people, but it is uncommon to have such a puzzle - if it was simply differing memories, I was the only one who remembered correctly out of about 30 people present, including the person who had been doing the talking.
But it's either that or day 2 was completely dreamed or imagined. I suppose.
Rolfe.