Few measuring scales seem to evaluate Mindfulness and emotion regulation in school aged children. This article aims to present four studies describing the construction and validation of two French measuring scales for children: French Emotion Regulation Scale for Children (FERS-C) and Mindfulness Scale for Children French version (MSC-F). We discuss the elaboration and choice of the items for each measure, examine their phrasing and comprehensibility from the children’s standpoint. The main sample consisted of 421 non-clinical, 6 to 12 years old children, who consented to fill out the measuring scales in order to test the factor structure. Additionally, we assessed and confirmed temporal stability and determined convergent validity. Results support that both scales appear to be reliable emotion regulation and mindfulness measures for school aged children. Results also reveal a relevant factor structure for both measures. The results of these studies support that the two scales are appropriate and useful measures of mindfulness and emotion regulation capacities for school aged children. In conclusion, we call for further research to improve and develop measures assessing child mindfulness skills in both clinical and research contexts.