Over the years, few studies have investigated the implementation of flipped classrooms focusing on students’ speaking performance and self-regulated learning (SRL). However, none of these studies was carried out using rich statistical and qualitative data to study both variables at the same time. This study, therefore, aims to (1) examine the effects of flipped classrooms with various technology tools on students’ speaking performance and SRL and (2) explore how students develop their SRL during the implementation process. The explanatory sequential mixed-method approach was used to obtain data from 53 tenth grade students, with 27 in the experimental group and 26 in the control group by employing a quasi-experimental design and an interview method. The result showed that the students taught by flipped classrooms had better speaking and SRL scores than their counterparts in the control group. In addition, the students developed their SRL through three phases, namely forethought, performance-control, and self-reflection, with four possible implications for English Language Teaching.