The focus of her research is on the concept of giftedness and how it is addressed as a matter of educational policy in a Swedish context. Her approach is from the perspective of Educational Philosophy with examples from both policy documents and teacher enactment in three types of classrooms; where explicit adjustments for giftedness are made, in the International Baccalaureate and in the Peak Programmes (spetsutbildning).
Sims runs courses in teaching with a gifted perspective. She is the editor and co-author of the anthology Särskild begåvning i praktik och forskning (2021).
Sims is one of Sweden’s representatives in the international network World Council for Gifted and Talented Children (WCGTC) and a member of ECHA, the European Council for High Ability. Currently, she is part of the formation of a Nordic network for research in the area, in cooperation with researchers from Norway, Denmark, Finland and Iceland.