This letter from the UKPA asks the DfES how they accommodate paruretics in the context of school drug testing. 

I'm contacting you as Chairman of the charity the UK Paruresis Association, which supports men and women who find it difficult or impossible to urinate in public. Our concern is not with the drug testing issue, but with the instruction to use urine testing. I don't think the DfEE realises that for a urine test to be effective against deception, it ...

This letter, from Nottinghamshire LEA, explains their position in relation to the condition and availability of school toilets. ​

 This letter, from the Health & Safety Executive explains their role in the availability and condition of school toilets. In summary, they do not have one, as children are not employees.

The scan below explains who the DfES say is responsible (from their point of view) for the management of problems with pupil toilets in state schools.