The popularization of the STEM educational model has also brought along the need for well-trained teachers. In this model, it is aimed to understand examples in real world and solve related problems. Of course, this depends on the development of critical thinking, creative thinking, researching and experimental skills. For these reasons, the opinions of the Physics-Chemistry teacher candidates regarding the preparation and implementation of STEM lesson plans were investigated. For this purpose, the preservice teachers were asked to form real life-related, information-based problems covering the acquisitions included in the high school programs and then they were expected to turn these into STEM lesson plans. The study is a descriptive study, one of the qualitative research methods. The data was collected via the forms developed by the researchers and including open-ended questions and one-to-one interviews. The data obtained were analyzed according to the content analysis steps, which is one of the qualitative research methods. When the analysis results were examined, it was found that the preservice teachers had difficulty in forming real life-related, information-based problems covering the acquisitions included in the high school programs and integrating them with scientific knowledge and in the engineering integration of STEM implementations and finding materials.