Those of us of a certain age probably had a computer studies teacher like old Cecil ... beard, bottle-bottom glasses, dubious dress sense ... and, given the inevitable mickey-taking, usually a crack shot with a board rubber!
The cache isn't at the posted co-ordinates. Neither is Mr C, who moved from Northants to rural Scotland when he retired, presumably in the hope of never seeing the dreadful little urswicks* he had to teach (of whom I was one) ever again.
(*"Little Urswick: The member of any class who most inclines a teacher towards the view that capital punishment should be introduced in schools." - The Meaning of Liff, Douglas Adams and John Lloyd)