Music teacher should be well acquainted with the vocal mechanisam. The vocal mechanism consists of three parts: a respirator, generator and resonator. Respirator includes respiratory tract and parts of bone-muscular part which allows the movements of breathing and lung. Breathing is a basic physiological vitel need of man. Phonatory organs are the generator: the larynx , laryngeal muscles, cartilage, true and false vocal cords, vocal cords opening - glotiss and laryngeal cavities. For phonation essential is connection between the larynx and the tongue, because the tongue movements lead to changes in the position of the larynx and the very form of the cavity of the larynx. The resonator includes cavities above the larynx, muscle structures and bone structures that help phonation and create the singing tone. During singing and demonstration of singing phrases, teacher must keep in mind the proper posture, breath, active usage of the diaphragm, appoggio, articulation and high impostation. 85 The main task of music teaching is to make voice agile, playful and resonant, and to enable its further development. Pupils imitate what they hear and what they see. Teachers need to be aware of all these components and they should help their students to be aware of them. Music teacher should be aware of all the potential damage caused by any incorrect singing. Teacher should correct all the vocal faults and missuse of the voice. This is not easy, teacher has a big responsibility, but all these problems should be processed with the warmth of teachers. This is supported by the open teaching model that allows teachers width in creating and designing lesson.