Professionals in all-day schools and in leisure time centres strive to purposefully extend the curriculum in the classroom with extracurricular activities. Extracurricular activities are more or less organized activities outside of the traditional teaching lessons during a regular school day and include supervised games, free play, and structured lessons organized before and after lunchtime. These activities are held at the school building. Such activities are added to children’s school days, making them more integrated to maximize social and cognitive learning for students and to enhance educational development. Education at school is extended in time and space, taught by professionals. The multi-professional cooperation among classroom teachers and extracurricular activities teachers is seen as powerful but can be rife with tension as professional boundaries are crossed. Data from interviews with classroom teachers and extracurricular activities teachers focusing on the meaning of extended education in newly organized all-day schools in urban Switzerland (n=32) and in Sweden (n=18) is analyzed using Grounded Theory Methods and viewed as a field for negotiating professional responsibilities. Despite different traditions in all day schooling, a lack of understanding of the other profession is a hindering factor for a symmetrical professional cooperation in both countries.