This master’s thesis is a qualitative case study which aims to investigate how the low-threshold orchestra operates at the practical level. Case study was held at the elementary school class. The key points of the study were to analyze: 1. how the teacher acts as the leader of the orchestra, 2. how pupils experience playing in ensemble and 3. how motivated pupils were to play the instruments. The study was carried out in the fourth grade of the elementary school of Padasjoki, Kullasvuori. The low-threshold orchestra was arranged there as part of an advanced course. The series of lessons including the orchestra practices were held in the class during 2.11.2021-14.12.2021. Research material consisted of a researcher-teacher’s observation diary during the study period mentioned above, questionnaires completed by the pupils at the beginning and at the end of study and a questionnaire completed by the teacher of the class. Based on the research observations the draft model of low-threshold orchestra practices was made. Research was centered at three key points: 1. developing the fourth grade’s orchestra practices, 2. studying the teacher’s creative action as a conductor and 3. studying pupils’ motivation to play in an orchestra. Starting points for this master’s thesis have been the objectives of the music education from the national curriculum guidelines. One of the most important objectives is to create a pedagogically diverse and flexible study module of music, which promotes different musical ways of working, interaction, musical group activity as e.g. playing in ensemble and other ways of doing music together, suitable for every student. The eagerness to learn, together with the atmosphere which encourages creative thinking and not forgetting the positive musical experiences – all of these things combined inspire pupils to develop their musical skills. My theoretical background is based on music education’s general surveys and on articles concerning the subject. My primary reference has been Kirsti Hämälainen’s licentiate study “Musiikinopettaja kapellimestarina” eng. Music teacher as conductor, which is the origin of the new term “kouluorkesterin johtajan ammattikuva” eng. the professional image of school’s orchestra leader. This term is about a music teacher’s conductor image which consists of the goals, the know-how, the attributes and the inner model. The task of leading the school orchestra consists of the previously mentioned parts combined with the planning skills, leadership skills and practical skills. Hämäläinen points out the special characteristics of the school orchestra which help us understand the singularity of the phenomenon. In this master’s thesis the school orchestra was localized in a class and by doing that the attempt was made to create an accessible and motivational study environment for the pupils. The findings of this master’s thesis point out that the motivation to play an instrument and the joy of playing in a group are dependent on conductor-teacher’s implemented working models which can consist of versatile methods, materials and different ways of working. This master’s thesis is related to music pedagogy and subject didactics so the material can be used as a tool for class teachers and music teachers who want to challenge themselves and their pupils with the new working models. The case study of this master’s thesis shows an option of how to realize the objectives of the music education from the national curriculum guidelines in practice, by playing in ensemble at the low-threshold orchestra in the classroom.