Yeah, I remember some horrible exams with questions like this. The problem is that the word 'interesting' is ambiguous. It's probably even worse than the 1-sentence "Prove [something difficult], from first principles" kind of question.
For me, what always worked was to pay special attention...
Heh, I'm very familiar with blank-brain incidents. What kind of question was it? For me, they only really occur with really badly written, unforgiving questions (e.g. 'State X, do Y etc.' without any notation or equations given).
As Gandalf said, 'worst' is a bad word, but I think it applies. My own worst fear was doing a huge amount of work and then not getting the grade to reflect that.
What's your worst fear about exams?
Panicking? Getting a mediocre grade? Not getting the credit you deserve? Not being admitted...
Maybe I should read the actual thread and not just the OP before responding. =)
Alright, it looks like you need some way to get the most out of your mind when it's already exhausted (or just partly 'clocked out' as you put it).
Just off the top of my head, here's what worked for me in these...
Hi Dave
From what you've said it seems more like a physiological/medical/stress management problem than anything to do with learning maths. Exhaustion could certainly be part of it, too - sometimes 'mathematical exhaustion' is hard to detect, and tends to accumulate.
I can't really give...