I think there are several problems with this case, and overall strongly support the School.
First thing is the obvious one - it seems obvious to me that the only reason such a big fuss has been raised is because the parents of the girl are the UK proponents of the whole ring scheme. I wonder what the girl, if asked in private, really thinks about this. There are deep questions of identity and family /peer-pressure here.
Second is that studies in the US have indicated the ring makes no positive difference anyway - there was a piece on the Guardian site the other day quoting that over 80% of 'purity' ring wearers do have sex before marriage.. as opposed to comparatively-few more that do anyway. However the ring-bearers tend to have higher incidences of STDs and/or unwanted pregnancies because the discussions on these (serious) matters do not or cannot happen in the context of this variety of upbringing. Blame the parents..? Yes.
And that's my concern here. I want my child to be educated enough, and loved enough, and know they're loved enough by their family (in case it goes ..wrong in any way, to be supported) to make informed choices about when and with whom sexual exploration first happens. In Britain we seem to have such a f*cked-up attitude to this milestone in our children's lives that on balance... we'd rather not know. By way of contrast, in Sweden (for instance) that first time..usually happens with the full knowledge of the parents, and at home. In a some car somewhere sometime, because yer parents'll kill ya, or ...safer. Think about that one for a while.
Just my 2p's worth.