Others have touched on the issues with fast clocks and the like, the real problem is no matter how large our layouts are, no matter how small the scale, we really can't mimic the operations of a real railroad based on real running times. Even with scale clocks it becomes problematic, if a real trip between A and B on the railroad takes 4 hours, and on our layout even at less than scale speed it takes let's say 10 minutes, we could use a 24/1 fast clock (240 minutes real time/24 to 1 fast clock=10 minutes), but that might not work well if for example timing when a yard engine has to deliver a car for pickup at a certain time.
If I was inclined to have operating sessions, I would base the fast clock time on how long the operating session was meant to be (IE the guys are coming over for 3 hours) and we want to simulate a typical 24 hour operations on the fictional or real railroad we model, we have a list of things we want to happen, including perhaps a timetable. In this example, it would be a 8 to 1 fast clock (it is where an app is handy, can set the ratio). From there,if we have a timetable for freight and passenger trains, and have a schedule based on this timetable for yard operations (ie making up trains before they leave, setting out cars, etc), then it simply becomes with the main trains, how do we simulate them given the relative small size of a layout....and the answer I have seen used is staging. So if for example, a freight train is supposed to leave at let's say 6am from some place (using fast clock), and at 7am is expected to be at some other point on the layout to allow a switching move to set out some cars, maybe pick some up, that using an 8 to 1 clock is roughly 7.5 minutes. If running directly that would take 30 seconds, then the train would have to 'hide' some place so that we could take it out of 'hiding' to arrive when it should (also could be on a siding, or also could be continuously running on a loop someplace else), and building a ratio simply on the real time it takes versus the timetable time won't work well (again, note, I have never operated like that, have seen it done and wondered even after watching it how they did it!).
As far as the kids not running it too fast, well, that one defies all logic
