This study examines pre-service teachers' Technological Pedagogical Content Knowledge (TPACK) development and analyses their conceptions of learning and teaching with technology. With this aim in mind, researchers designed and implemented a computer-based mathematics course based on a TPACK framework. As a research methodology, a parallel mixed method approach was used. The data were collected from 71 pre-service teachers taking the course. The TPACK survey, a semi-structured interview, and evaluation scores of pre-service teachers' microteaching performance, which also included analysis of lesson plans, were used as data collection instruments. The findings indicated that the implemented instructional processes affected pre-service teachers' TPACK development positively. There were significant differences before and after the course implementation concerning Technology Knowledge, Technological Content Knowledge, Technological Pedagogical Knowledge, and TPACK in general. Qualitative findings support and overlap the statistical inferences. There should be more courses which require pre-service teachers to develop computer-based instructional materials and use their materials with microteaching sessions. Instructors of faculties of education should use technology in their instructional environments not only for presentation purposes.