Back in the '60s, my school CCF only had an Army section. We had a few ancient Mauser rifles, about half a dozen old SMLEs, dozens of Lee-Enfield No4 rifles, a jungle carbine, half a dozen DP Bren Guns and a few Sten Guns. Plus a couple of revolvers modified to fire only .22 blanks, some 2" mortars and 3.5" rocket launchers and some .22s for range firing. All were originally housed in a pre-fab building, but later rules meant that they were moved into a purpose-built armoury in which live and blank rounds were also stored.
On Field Days we would be bussed to the Quantocks with our .303s, although we also took the DP Brens plus old-style football rattles which the second man on the Bren would whirl furiously to simulate firing sounds. The .303s also went with us to Summer Camps on Exmoor - no-one thought twice about teenagers toting rifles around the hills back then.
The Stens also had some blank-firing barrels - these were basically a barrel with an internal tapered constriction which would allow gas pressure from a blank to chamber the next blank round, simulating the real weapon - but of course a Sten with a blank barrel couldn't be used to fire real 9mm rounds.
One of the blank barrels had developed a crack, so one of our number took it to a local gunsmith for repair. When it was ready, I went with my colleague to collect it. Little did I know it, but in his briefcase he also had the rest of the weapon. So there we were in the local gunsmiths, in school uniform - and my chum pulled out the Sten to check that the barrel fitted OK. It did, so off we went back to school with a Sten gun in a briefcase! No-one else in the gunsmiths thought anything about this, but I've always wondered what the local rozzers would have said if they'd known. Back to school, down to the bottom fields with some blank 9mm ammo to test the thing. It worked briefly 'da-da-da-clunk', but the barrel had broken again and that was that!
But it wasn't the most hazardous item we had at school. That was actually a 1955-era Switchboard Magneto Mk 10 portable telephone exchange, which had replaced the WW2 'Universal Caller 10 lines' exchange, which was like something out of Blackadder and weighed over 30lb. The reason the SM10 was so dangerous was that it had a lot of luminous painted labels over the line sockets, which meant that it was more radioactive than anything kept securely in the Physics Lab.
These days things sound a lot safer, but perhaps more boring?