Mathematical problem solving is one of the most valuable aspects of mathematics education. It is also the most difficult for elementary-school students (Verschaffel, Greer, & De Corte, 2000). Students experience cognitive and metacognitive difficulties in this area and develop negative emotions and poor motivation, which hamper their efforts (Kramarski,Weiss, & Kololshi-Minsker 2010). The ages of nine through 11 seem to be the most critical for developing attitudes and emotional reactions towards mathematics (Artino, 2009). These metacognitive and motivational-emotional reactions are fundamental aspects of self-regulated learning (SRL), a non-innate process which requires systematic, explicit student training (Pintrich, 2000; Zimmerman, 2000). Most self-regulation studies about problem solving tend to focus on metacognition; few have explored the motivational-emotional component. This study developed, examined, and compared two SRL interventions dealing with two components of self-regulation: metacognitive regulation (MC) and motivational-emotional regulation (ME). The study conducted a two-group intervention to examine the possible effects on the self-regulation aspect of student problem-solving ability of increasing one group's metacognitive awareness, while leaving the motivational-emotional component alone, and of increasing the motivational-emotional awareness of the other group, while leaving metacognitive awareness alone. It also examined the contribution of these components to students' problem solving and self-regulation. Participants were 118 fifth-grade students randomly assigned to two groups. The groups completed self-regulation questionnaires before and after intervention to examine metacognition, motivation, and emotion. Students also solved two forms of arithmetic series problems: verbal and numeric. After intervention, a novel transfer problem was also examined. The intervention consisted of 10 hours over five weeks. Following intervention, the groups exhibited similar improvements in all problems. The MC group performed best in metacognitive self-regulation, and the ME group performed best in certain motivational-emotional aspects of self-regulation. Research implications are discussed.