Mathematical problem solving is one of the most valuable aspects of mathematics education and the most difficult for elementary school students. Cognitive and metacognitive difficulties in this area cause students to develop negative attitudes and emotions as affective reactions, hampering their efforts and achievements. These metacognitive and meta-affective reactions are fundamental aspects of self-regulated learning (SRL), a non-innate process that requires systematic, explicit student training. This study investigated the impact of two self-regulation programs among young students (Grade 5)--metacognition (n = 64) and meta-affect (n = 54) versus a control group (n =53)--on enhancing achievements in mathematical verbal problem solving and a novel transfer task, as well as metacognitive and meta-affective regulation processes of a focus group during a thinking-aloud solution. Mixed methods indicate that students who participated in the metacognitive and meta-affective intervention programs presented similar but higher achievements than the control group. Additionally, during the thinking-aloud solution, students from each group broadly implemented the self-regulation processes they were trained in, while consistently referring to all the self-regulation phases. The current study makes an important contribution to practical implications for students with diverse abilities.