Theoretischer Hintergrund: Die motorische Leistungsfähigkeit (MLF) spielt eine zentrale Rolle in der Kindesentwicklung. Über den Verlauf der MLF über die Grundschulzeit in Abhängigkeit auffälliger motorischer Leistungen im Vorschulalter liegen nur wenige Befunde vor. Fragestellung: Liegen unterschiedliche Entwicklungsverläufe derMLF bei Kindern mitmotorisch auffälligen Leistungen in der Fein- und Grobmotorik vor? Methode: Innerhalb einer Längsschnittstudie wurden die motorischen Dimensionen Kraft, Ausdauer, Schnelligkeit, Koordination und Beweglichkeit von Grundschulkindern (N=424) jährlich untersucht und mittels Varianzanalyse mit Messwiederholung geprüft. Ergebnisse: Kinder, die vor Schuleintritt grob- oder feinmotorische Auffälligkeiten (9-15 %) aufwiesen, blieben in ihrer motorischen Entwicklung deutlich hinter motorisch unauffälligen Kindern zurück. Diskussion und Schlussfolgerung: In der Folge können sich erhebliche Einschränkungen für die Alltagsmotorik und das Erlernen komplexer Bewegungen ergeben. Um gleiche motorische Startbedingungen für die betroffenen Kinder herzustellen, stellt die Erweiterung der bewegungsbezogenen Förderung der MLF vor Schulbeginn einen notwendigen Ansatz dar. / Theoretical Background: Motor performance is an important matter in the health-related development of children, particularly for perception and for establishing a personal and material environment using physical activity. Developmental coordination disorders in preschoolaged children may relate to lower levels of fine and gross motor development. Short-term longitudinal studies revealed that preschoolers with motor deficits fall behind in their overall motor performance during the 1st and 2nd grades of primary school. Moreover, the years at primary school are a meaningful stage in life for children because of its rapid progression in motor-learning capability. Objective: Regarding children in primary school, little is known about the effects of developmental coordination disorders on the grade-related progression of basic motor abilities (i.e., flexibility, strength, endurance, speed of movement, coordination). This study analyzes the motor performance development of children over the period of primary school. Method: Using a longitudinal study design (KOMPASS-2 Study), we examined motor ability development in a sample of N = 424 primary school-aged children (n = 218 girls, 51.4%). To assess levels of motor abilities, we used the German Motor Test (DMT 6-18). Based on standard screening for school entry, children were separated into two groups based on the status of their fine and gross motor development. Changes inmotor ability levels were analyzed via robust repeated measures analyses of variance (rmANOVA) regarding developmental group effects, school timeframe effects, and interaction effects. Results: 9% (n = 39) of the children were classified with a gross motor disorder, and 15% (n = 62) of the children were classified with a fine motor disorder. The statistical analyses with rmANOVA demonstrated that children with developmental coordination disorders regarding gross or fine motor developmental status showed lower motor-ability levels on all test tasks compared to children without disorders. Particularly gross-motor disordered children achieved significantly lower motor-ability levels regarding coordination under time constraint (jumping sideways) and coordination during dynamic precision tasks (backward balancing). However, motor-ability levels increased significantly over time for both developmental status groups. Discussion and conclusion: Children with developmental coordination disorders may experience substantial restrictions to meeting daily physical activities and motor learning of complex movements. To create equal motor developmental conditions for children just starting school, it is necessary to promote physical activity in general. Interventions should regard a set of coordination tasks that require children’s attention and speed during movement. Measuring the motor abilities of primary-school-aged children once a year should be an integral part of communal health monitoring.