It is here, too, in the section entitled, “Play or Spontaneous Expression and Practice of Every Kind” that Froebel begins a general classification of boy’s play: “The plays, or spontaneous occupations, of this age are of three kinds, they are either (_a_) imitations of life, or (_b_) spontaneous applications of what has been learned, or they are (_c_) perfectly spontaneous expression with all kinds of material. These last are either governed by the material, or by the thought and feeling of the human being.… They may be and are either Physical plays, exercising strength and dexterity, or else mere buoyancy of life; or Sense plays exercising the hearing, e.g. in hiding games, etc., or the sight, as in shooting plays or colour plays, etc.; or Intellectual plays, games of reflection and judgment, e.g. draughts, etc. As such they are already arranged, but the true aim and spirit of the play is rarely understood and the games are seldom managed according to the needs of the boy.”--_E., p. 304._ This general classification is very much the same as that of Groos, who divides Play first into two main classes, viz. Playful Experimentation and Playful Exercise of the Second or Socionomic Order. Under the first heading come I. Playful Activity of the Sensory Apparatus; II. Playful Use of the Motor Apparatus; and III. Playful Exercise of the Higher Mental Powers. The first two correspond to Froebel’s Sense Plays and Physical Plays, and the third to his Intellectual Plays. Under the second heading, Groos brings Fighting Plays, which as we have seen Froebel attributes to the unconscious desire to measure and increase strength; Imitative Play, which to Froebel is the child’s way of learning by action; Love Plays of which Froebel takes no notice at all, and Social Play. Under this comes what has been given as to the importance of Playgrounds, and much of what Froebel wrote as to the Kindergarten Games. For instance, as part of the work of the students in his Training Course comes: