The smells are different between primary and secondary school.  You go from rotting plimsolls (and the feet therein) to various acids waiting to be turned into stink bombs, freeze the head boy or tools for encouraging pyromania.

You weren’t allowed matches at primary school, let alone Bunsen Burners you’d try and emulate a North Sea oil rig fire with.  The only way I’d have started a fire in my Balham primary school would have been by hitting my Glockenspiel too quickly.

I remember the first moment I entered my Tooting secondary school chemistry lab, with its associated smells.  Was I going to fall off the stool?  Would I get to wear the long white coat (I assumed the physics teacher had just come from umpiring a school cricket match)? Was I going to end up being part of the Quatermass Experiment?

During one physics lesson we learned about propulsion from fireworks to manned spacecraft.  I remember thinking to myself: “Well, it’s not rocket science, is it?”  Which, of course, it was, and one of the many reasons I failed all my science exams.  Or wasn’t the first man on the Moon.