Pupils may be received in the Sunday School classes of any Church of Christ, Scientist, up to the age of twenty years, and by transfer from another Church of Christ, Scientist, up to that age, but no pupil shall remain in the Sunday School of any Church of Christ, Scientist, after reaching the age of twenty. None except the officers, teachers, and pupils should attend the Sunday School exercises.
Mary Baker Eddy Manual of The Mother Church Article XX, Section 1
A wonderful expectancy flows through Mary Baker Eddy's opening words for Sunday School in the Church Manual. Expectancy that children and teenagers will always find Sunday School classes ready to receive them in The Mother Church and in its branches around the world.