Mad on the Science Blook Roof

Says Steve Webb who sent the photo:

I pretty sure that it was taken at the end of my exams, probably A level, which would date it to 1962, which would tie in with the MAD theme, (as in Mad Magazine). I can't for the life of me remember how we got to the science block roof, well, not me, I took the photo from the ground !

I don't remember who the lads were who went on the roof, and can't recognise any from the fuzzy photo