5. =The Intermediate Department.= Here the pupils are from twelve to sixteen years of age. The classes should be small, generally of six boys or girls, never more than eight. This period in life is known as early adolescence, and calls for careful direction by wise teachers. In the Intermediate Department the great biographies of the Bible should be studied, either as the regular or the supplemental lessons; also the heroic lives of leaders in the history of the Church, of foreign missionaries, and of men and women who have labored in the home fields. Boys and girls in this stage of life are instinctively hero-worshipers, and before them should be set high ideals of character and service. Special effort should be made in leading the scholars to personal consecration to Christ and to union with the Church; for if the great decision be not made before the age of sixteen is reached, there is great danger that it will never be reached. But that decision should include more than a formal profession. It should embrace a full surrender to the will of Christ, an inward, conscious spiritual life, an aim for completeness of Christian character, and especially a willingness to work for God and humanity. Youth is a season of ardor and of energy, a period of lofty ideals and noble endeavor. All those active powers of the youthful nature should be guided into channels of usefulness. The true twentieth century disciple of Christ is not one who lives alone feasting his soul on God, but one who stands among his fellow-men, eager to aid in the world's betterment. 6. =The Senior Department.= This is the preferable title, although some organized schools call it the Young People's Department, and restrict the word Senior to the classes of fully adult age. Still others call it the Assembly, and give it an organization independent of the Sunday school.[7] The age of entrance should be sixteen, except with some who in stature and mind are mature beyond their years. It is imperative, as we have already seen, that at the door of this department the young people should leave their former teachers, and should not form new Senior classes, but as individuals enter classes already established. This department includes the members of the school between sixteen and twenty years of age; not that members of classes must necessarily leave them at twenty, but that men or women above that age entering the school should rather join the Adult Department. The classes may be as large as the arrangement of rooms will allow; larger where each class can have a separate room, which is the ideal plan. Generally, young men and young women should be in separate classes. The teacher of a young men's class should be a man whose character will inspire the respect and win the fellowship of his class. The teacher of the young women's class will generally be a lady, although often men have been successful teachers of young women.