My experience of visiting other ME clubs is limited, but each time I have been made welcome, and shown around.
With regard to CRB, my understanding is that a check is required for REGULAR contact. But it gets stupid, at church a school teacher, was required to have one to teach youngsters in Sunday School.
Officialdom believed that she became a pedophile between 5.00 pm Friday and 9:00 am Monday!
I know that Hereford SME (live too far away to be a member) encourages youngsters, even having a separate workshop where they can make useful parts for the club, and are taught to work as guards, and eventually drivers.
When PSME had a track, youngsters were allowed to drive when the public passenger hauling was not in progress.
During the latter years of my employment, I often mentored undergraduates during their gap year. The ones who took an interest in learning how things worked, and how things could go wrong, did very well. Some were eventually invited to go to our US parent, to show and advise on what they had learned, so that their practical and theoretical skills could be used.
Only two, as I recall, thought that such things were beneath them, and they turned out to be neither use nor ornament.
In general, the UK public never realise that what they have and use, is the result of the work and skills of Engineers; unlike the continent, where engineers are held in esteem. Being a hedge fund manager is a poor qualification for changing a wheel on the side of a motorway at 2:00 in the morning!
Rant over, off to put away soap box.
Howard