Understanding scientific models and practicing scientific modeling have been emphasized and advocated in science learning. Although teachers have been perceived as shaping their students' understanding of the nature of science, they have been recognized for their lack of understanding of scientific models. This study explores middle school science teachers' and ninth-grade students' performance in terms of their understanding of scientific models and their construction and evaluation of these models. The study participants comprised 95 science teachers and 608 ninth-grade students. To investigate the students' understanding of scientific models, they were asked to fill out a Students' Understanding of Models in Science survey. To explore the students' model construction and evaluation, they were asked to explain three different magnetic phenomena and to provide the criteria they used to evaluate the scientific models. The results show that the teachers' performance on these three aspects was significantly better than that of the students. However, this study indicated that teachers have similar problems as students in terms of understanding theoretical representations of scientific models and practicing model construction. Moreover, those teachers who had a better understanding that scientific models are not the replica of target events could develop higher levels of models while students with more understanding that scientific models are the replica of target events were able to develop higher levels of models. The findings of the study contribute to a better understanding of the gap between teachers and students, which will be crucial for designing a better modeling-based curriculum.