This study aimed to analyze views of mathematics student-teachers on teaching practice in classroom contexts by subsuming following the new didactic triangle, which was used as a conceptual framework: (1) Teaching Process, (2) Learning Process, and (3) Thinking Process. A participative research design was employed for the research methodology. The participants included seven fourth-year student-teachers, a purposive group of a case study that had been teaching practice in schools of the mathematics teacher education program for two weeks. They voluntarily participated in schools using Lesson Study and Open Approach and collaboratively designed lesson plans coached by researchers. After two-week teaching practices in school contexts, they were asked to reflect on their teaching practice covering (1) whether their teaching practices are accomplished, show some evidence of students' ideas, (2) identify problems found in their teaching practice, and (3) identify improving aspects of teaching practice for subsequent lessons' improvement. Results of the study showed that the mathematics student-teachers' views are reflected on their teaching practice in the actual classroom context following the aspects of the new didactic triangle and correlate with teaching mathematics through problem-solving, which is a mainstream and widespread pedagogical approach.