Valid feedback is essential for the administrators, educators, parents and, of course, for children to be able to steer their development in a sustainable way. Key influential theorists such as Montessori, Piaget, Vygotsky, and others all used observations extensively to understand how children learn and use knowledge about children's learning to improve pedagogies and children's lives. However, most adults including teachers in the ECEC settings have not always observed children and tracked their growth.The grantees of Hong Kong Research Grants Council, Dr James Ko, Professor Doris Cheng, and Dr Jyrki Reunamo, have collaborated to find relationships between young children's involvement, adaptation and agency in early childhood settings through systematic observations. More than 100,000 observations were documented in research and professional development programs conducted in Finland, Taiwan and Hong Kong. By using simple cross-tabulation, researchers and teachers can obtain information about the context-specific aspects of learning, emotions and social relations. For example, children’s strategies to confront bullying were connected to their observed activities (Reunamo, Ko, Cheng, Lee, Wang, & Salminen, 2016). Agency and openness orientations observed in children were found affecting their differential development trajectories including their school readiness (Ko, 2015) and some children may show a higher risk in certain aspects of growth (Ko, 2015; Reunamo et al., 2016). It is well-known that "play" related activities in Hong Kong are very different from Finnish one (Cheng & Stimpson, 2004, Cheng, 2012), though western teaching approaches are translated in the Hong Kong early childhood curriculum (Cheng, 2006). By systematic observations, Cheng and Chen (2017) also showed that children in play-based activities showed the strongest class involvement. Recently, three researchers have developed self-accessible training materials with video clips and demonstrated how