Schedule 12
1(1)Section 91(1), so far as relating to sex, does not apply in relation to a single-sex institution.
(2)A single-sex institution is an institution to which section 91 applies, which—
(a)admits students of one sex only, or
(b)on the basis of the assumption in sub-paragraph (3), would be taken to admit students of one sex only.
(3)That assumption is that students of the opposite sex are to be disregarded if—
(a)their admission to the institution is exceptional, or
(b)their numbers are comparatively small and their admission is confined to particular courses or classes.
(4)In the case of an institution which is a single-sex institution by virtue of sub-paragraph (3)(b), section 91(2)(a) to (d), so far as relating to sex, does not prohibit confining students of the same sex to particular courses or classes.
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The rules on single-sex schools are deliberately flexible, to allow, for example, for the fact that in sparsely populated areas, it might otherwise be difficult for both sexes to get local access to a full range of subject matter teaching. 3(a) allows for 'exceptional' opposite-sex admissions with no further explanation. The school might try to rely on this.