This study determined the effectiveness of Constructivist teaching method on students' performance in metalwork in technical colleges in Yobe State, Nigeria. The study adopted quasi-experimental research design in which intact classes were used. Two research questions were raised to guide the study, two hypotheses were formulated and tested at 0.05 level of significance. The sample size was 58 students selected from the two technical colleges in the state. The instrument used for data collection was Metalwork Performance Test (MWPT) which was validated by three experts with a reliability coefficient of 0.82. Mean was used to answer the research questions while ANCOVA was employed to test the hypotheses at 0.05 level of significance. The study found that students in experimental group performed higher than those in control group. This implies that constructivist teaching method is more effective than lecture method in teaching measurement and marking out; and drilling process. The study therefore recommended that Metalwork teachers should be trained to use constructivist teaching method; also the National Board for Technical Education should consider reviewing its curriculum to incorporate constructivist method of teaching her programs.