Where the parent of any pupil who is a boarder at any public school F1. . . or other educational establishment under the management of an education authority F2... requests that the pupil be permitted to attend worship in accordance with the tenets of a particular religious denomination on Sundays or other days exclusively set apart for religious observance by the religious body to which his parent belongs, or to receive religious instruction or to practise religious observance in accordance with such tenets outside the working hours F3of the school or other educational establishment, the education authority shall make arrangements for affording to the pupil reasonable opportunities for so doing, and such arrangements may provide for affording facilities for such worship, instruction or observance on the premises of the school F1. . . F4or other educational establishment, so however that such arrangements shall not entail expenditure by the education authority F5....