Our study investigated 3 metacognitive approaches provided during different phases of learning technological pedagogical content knowledge (TPCK) in a Web-based learning environment. These metacognitive approaches were based on self-question prompts (Kramarski & Mevarech, 2003) which appeared in pop-up screens and fostered the Self-Regulated Learning (SRL) of pre-service teachers (n = 144) through 1 of the 3 learning phases (Zimmerman, 2000): "planning," "action and performance," and "evaluation." Four measures (pre/post) were administered in the study: SRL self-report questionnaires in the contexts of pedagogical learning and teaching and TPCK in the comprehension and design lessons. Mixed quantitative and qualitative analyses showed that fostering students' SRL through the "evaluation" phase was the most effective for the pre-service teachers' perceived SRL in both the learning and teaching contexts and for their TPCK (comprehension and design lessons). Furthermore, students from the planning approach outperformed the students from the action approach in most of the SRL and TPCK measures. (Contains 1 figure and 5 tables.)