I took DS on a day trip, if anyone's school doesn't go.
We got a day return on EasyJet, it was about £18 or £18 each, each way, but the cheapest I can see now are about £50 day return. We took a flight out at about 7.30 am from Gatwick , and an early evening flight home.
There is a bus or tram directly from Geneva airport to the CERN gates, all very easy to navigate. Go on the CERN website and you can see details of guided tours for individuals. There are 2 big exhibitions, we saw the computer that Tim Berners-Lee used to invent the internet, as an communications system for within CERN. My nephew was on placement as a student there and he showed us around, we went to the testing centre where they test sections of the LHC, and we saw the main control room where they use computers to direct the particles round the differnt parts of the accelerators. And we went to a couple of the labs around the LHC. I'm not sure what it is possible to do on a guided tour organised by CERN, but I think the school trips go to those places.
We even had time to go down to central Geneva by the lake for an ice cream and coffee before heading back to the airport - again all completely easy on the tram system, and we passed the UN HQ.
The food in the canteen was v expensive - Switzerland is £££ - but it's once canteen for top physicists and visitors alike. They kept leaping up to rush to labs, according to what was being shown on the monitor screens.
It was a BRILLIANT day out.