The need for constructivist classroom environments in mathematics teaching cannot be ignored in order for sustainable development to continue. One of the most important applications of constructivist classroom environments in mathematics education all over the world is mathematical activities. The proficiency of pre-service mathematics teachers in developing activities will support constructivist classroom environments. In this study, it was aimed to reveal pre-service mathematics teachers' thoughts about what points they consider while they develop activities for mathematics courses. With this aim, an open-ended question was addressed to 23 pre-service teachers taking education at Elementary Mathematics Teaching program of a state university and having received the elective course of "Activity Development in Mathematics Teaching." The obtained data was analyzed via the content analysis method. As a result of the study, it was determined that the participant elementary pre-service mathematics teachers expressed the points which they considered while developing activities with a total of 161 sentences or words. The statements obtained as a result of the analysis of the answers which the pre-service teachers gave to the research problem were gathered and examined under five sub-themes, namely "general," "purpose," "scope," "planning" and "the role of the teacher in practice." In respect of the points which elementary pre-service mathematics teachers considered while developing activities for mathematics courses, participants considered while developing activities for mathematics courses, they were observed to use statements which were mostly related to the sub-theme of "the role of the teacher in practice." When it was evaluated in general, it has been observed that the participant elementary pre-service mathematics teachers are generally aware of the points to be emphasized. However, due to the low number of pre-service teachers who emphasized some points, it was concluded that they did not have enough knowledge about developing activities.