(1)    The Secretary of State shall by regulations—

(a)    impose a limit on class sizes for infant classes at maintained schools; and

(b)    specify the school years in relation to which any such limit is to have effect.

(2)    Any limit imposed under this section shall specify the maximum number of pupiIs that a class to which the limit applies may contain while an ordinary teaching session is conducted by a single qualified teacher.

(3)    Subject to subsections (4) and (5), regulations under this section shall be so framed that—

(a)    the maximum number specified in pursuance of subsection (2) is 30, and

(b)    that limit has effect in relation to the 2001–02 school year and any subsequent year.

(4)    Regulations under this section may—

(a)    provide for any limit imposed under this section to take effect—

(i)    at the same time in the case of each of the age groups into which the pupiIs in infant classes fall, or

(ii)    at different times (which may be earlier than the beginning of the school year mentioned in subsection (3)) in the case of different such age groups;

(b)    provide that, in any circumstances specified in the regulations, any such limit either is not to apply or is to operate in such manner as is so specified.

(5)    The Secretary of State may by order amend subsection (3)—

(a)    by substituting for “30” such other number as is specified in the order; or

(b)    by substituting for the reference to the 2001–02 school year a reference to such other school year as is so specified.

(6)    Where any limit imposed under this section applies to an infant class at a maintained school, the local education authority and the governing body shall exercise their functions with a view to securing that that limit is complied with in relation to that class.