It is well known that the regulation of processes is an important factor in problem solving from Grade 7 to university level (cf. Mevarech & Kramarski, 1997; Schoenfeld, 1985). We do not, however, know much about the problem-solving competencies of younger children (cf. Heinze, 2007, p. 15). Do the results of studies also hold true for students below Grade 7? The study presented here strongly suggests that metacognition and process regulation is important in Grade 5 as well. The research questions are: How do the (more or less successful) problem-solving processes of fifth graders occur? What is the impact of metacognition and self-regulation on these processes? Are the transitions between phases in the problem-solving process closely connected to metacognitive activities? An analysis of approximately 100 problem-solving processes of fifth graders (aged 10-12) from German secondary schools will be used to help answer these questions. The videotapes that supplied the raw data were parsed into phases called episodes using an adapted version of the "protocol analysis framework" by Schoenfeld (1985, ch. 9). The junctures between these episodes were additionally coded with the "system for categorizing metacognitive activities" by Cohors-Fresenborg and Kaune (2007a). There is a strong correlation between (missing) process regulation and success (or failure) in the problem-solving attempts. Concluding suggestions are given for the implementation of the results in school teaching. These suggestions are currently being tested.