The purpose of this study was to investigate teachers' perceptions, practices, and the challenges they encountered in implementing constructivist teaching and learning approaches (CTLA). For this purpose, a mixed methods research approach with concurrent mixed methods design was used. The study gathered data from both primary and secondary sources. Six woredas were randomly selected from the 16 woredas in the West Gojjam Zone as sample sites. From these woredas, 178 middle school social studies teachers (101 males and 77 females) were chosen through random sampling, while 360 students (170 males and 190 females) were selected using systematic random sampling techniques. Quantitative data were collected through close-ended questionnaires, while qualitative data were gathered using interviews, observations, and document reviews. The quantitative data were analyzed using descriptive and inferential statistical methods, including frequencies, percentages, means, standard deviations, one-sample t-tests; independent samples t-tests, one-way ANOVA, and multiple regression analysis. On the other hand, qualitative data were analyzed using case-based thematic analysis, detailed descriptions, and narrative techniques to provide a comprehensive understanding of the findings. The findings revealed that social studies teachers in the West Gojjam Zone held positive perceptions of both constructivist and traditional approaches to teaching and learning in social studies education. Interviews further revealed that teachers held supportive perceptions regarding the adoption of constructivist teaching and learning principles in the classroom. The study revealed that teachers' perceived practice of CTLA dimensions fell short of expectations, except for the student negotiation sub-scale. This finding was further supported by classroom observations, which indicated that most teachers predominantly relied on traditional teaching and learning methods. The study found a strong positive relationship between social studies teachers' constructivist perceptions and practices. Constructivist perception emerged as the strongest predictor of these practices. The regression model (R² = 0.552) showed that 55.2% of the variance in CTLA implementation was explained by factors such as traditional and constructivist perceptions, gender, qualifications, and teaching experience The major challenges hindering the implementation of CTLA included insufficient commitment from teachers and students, differing pedagogical preferences, and a lack of collegial exchange among social studies teachers. Additional barriers included inadequate training on the CTLA related curriculum, a shortage of learning resources, ineffective time management, and a lack of constructivist skills. The study recommends that education experts from West Gojjam, in collaboration with instructors from teachers' colleges and universities, organize targeted professional development programs and focused training sessions. These initiatives should aim to better align teachers' perceptions of constructivism with their classroom practices, ultimately enhancing the effectiveness of teaching and learning in the region.