In reply to Peakpdr:
I work at the Roaches with groups and climb there myself regularly. It is one of my local crags. I also do voluntary work there too. I don't share your view. It's not the crap whole you describe by any means and suggest it's no worse than anywhere else.
Yes, dog crap is bad and human crap is worse. I think in 20 years I have seen the later about twice while working at the Roaches. Likewise rubbish including disposable bbq's is bad. No harm in taking it away yourself even if it's not yours. That's exactly what we do as volunteers if needs be.
Any group I have worked there with have always been with responsible teachers/staff and we always ensure they leave as found and nothing is left behind. Can't say I have worked there with a particularly obnoxious group ever. Sometimes language is less than to be desired but that is all and then they respond to requests to tone it down.
As for explicit drawings yes I agree entirely. No way should that happen. But that would never be toerated with a group I work with as myself, other instructors or teachers/staff would be there immediately to stop it and would never allow such behaviour. It would be noticed before the damage was done. So don't necessarily put the blame for that on school groups.
As you say school groups don't come in uniform but it is easy enough to find the bus or minibus they arrive on which often has the school name or bus company name on it so it wouldn't be so difficult to make a complaint if you see something you don't like. In addition to that approach the instructors, teachers/staff in control of the group and let them know what you have seen. I for one would be receptive and listen to your concerns as would any other instructors I work with. Often as instructors we have the logo of the company we are working for on us so again that is another means by which to identify us/the group.
It's not in our interests as leaders/instructors to have disreputable groups on our hands so we take every care to respect the environment we work in and other users either groups or members of the public including other climbers.
It sounds to me like you had a particularly bad day and I would suggest you don't turn your back on the Roaches and return another day to be reminded what a great place it is and use it respectfully yourself.