Research has shown that the Swedish results of education have fallen continuously since 2000. It has been shown that there are differences in performance between native students and immigrant students. National Centre for “Swedish as a second language” indicates that Swedish schools fail to give all students an equal and high quality education. Then Swedish as a second language education can be organized in two different ways a wonder arise if it can depend on how teachers´ conditions in teaching reveals in these. This study aims to lighten primary school teachers' views on the opportunities and difficulties in second language teaching, which can be organized in two different ways, "separate" and "within the framework of the class". The research questions of the study are, 1) What requirements do teachers perceive that the curriculum for “Swedish as a second language” requires? What opportunities and difficulties can be seen here? 2) What trade-offs are made in the planning of teaching and how are these applied in the teaching of “Swedish as a second language”? What opportunities and difficulties can be seen here? 3) What conditions for scaffolding and interaction do teachers create in teaching "Swedish as a second language? What opportunities and difficulties can be seen here? By using Shulmans theory PCK (Pedagogical Content Knowledge) it manages to visualize teacher language didactic choices within the subject “Swedish as a second language”. Through a qualitative study based on interviews and observations, the result shows that both teachers reason about a range of language didactic choices, opportunities and solutions, but these could not always be transformed and seen in practice. During the observations, it became clear that the “Swedish as a second language” teaching structural conditions both enabling and impeding teachers to conduct effective teaching. In this case, separate teaching came to be ineffective because they did not have a language development perspectives in school, thereby the subject was stigmatized.