(1)For the purposes of this Part, the key stages in relation to a pupil are—
(a)the period beginning at the same time as the school year in which he attains the age of six and ending at the same time as the school year in which the majority of pupils in his class attain the age of seven (“the first key stage”),
(b)the period beginning at the same time as the school year in which the majority of pupils in his class attain the age of eight and ending at the same time as the school year in which the majority of pupils in his class attain the age of eleven (“the second key stage”),
(c)the period beginning at the same time as the school year in which the majority of pupils in his class attain the age of twelve and ending at the same time as the school year in which the majority of pupils in his class attain the age of fourteen (“the third key stage”), and
(d)the period beginning at the same time as the school year in which the majority of pupils in his class attain the age of fifteen and ending at the same time as the school year in which the majority of pupils in his class cease to be of compulsory school age (“the fourth key stage”).
(2)The head teacher of a school may elect, in relation to a particular pupil and a particular subject, that subsection (1) shall have effect as if any reference to the school year in which the majority of pupils in that pupil’s class attain a particular age were a reference to the school year in which that pupil attains that age.
(3)If at any time, in the case of a pupil of compulsory school age, subsection (1) does not, apart from this subsection, apply to determine the period within which that time falls, that subsection shall have effect as if—
(a)in the case of paragraphs (a) to (c), any reference to the school year in which the majority of pupils in that pupil’s class attain a particular age were a reference to the school year in which that pupil attains that age, and
(b)in the case of paragraph (d), the period were a period beginning at the same time as the school year in which he attains the age of fifteen and ending when he ceases to be of compulsory school age.
(4)The Secretary of State may by order—
(a)provide that, in relation to any subject specified in the order, subsection (1) shall have effect as if for the ages of seven and eight there specified there were substituted such other ages (less than eleven and twelve respectively) as may be specified in the order, or
(b)amend subsections (1) to (3).
(5)In this section “class”, in relation to a particular pupil and a particular subject, means—
(a)the teaching group in which he is regularly taught in that subject, or
(b)where there are two or more such groups, such one of them as may be designated by the head teacher of the school.