The study aims to examine the effect of concept cartoon supported lesson plan development practices based on the 5E learning cycle model on the non-routine problem solving skills and attitudes towards mathematics teaching of primary pre-service teachers, to determine the level of problem construction, to evaluate the texts in the problems constructed with concept cartoons developed by primary pre-service teachers in terms of text writing success level and to reveal their opinions about the practices. The study utilized a nested design, which is a mixed-method research approach, and employed a convenient sampling method for participant selection. Data collection was carried out using the attitude towards mathematics teaching scale, problem solving scale, interview form, and lesson plans developed by primary pre-service teachers. The data were evaluated by content analysis, t-test for related samples, descriptive analysis, progressive scoring scale, problem posing skills scoring key, grading scale. Significant enhancements in attitudes toward mathematics teaching were observed in favor of the post-test, with opinions categorized into six distinct groups, highlighting challenges encountered during the evaluation phase and the process of problem posing. It was ascertained that the overall level of achievement in text creation was generally deemed satisfactory.