The Middle Years Development Instrument is a population-level measurement tool that can be used to assess, understand, and inform decisions about children’s development for the middle years age group. It is a self-report survey completed by children in Grade 4 and Grade 7 that asks them about their experiences both inside and outside school. The survey measures social and emotional development, connectedness, school experience, physical health and well-being, and the use of after-school time. Currently, this survey is administered to children at sites in BC, and this funding will support the addition of eight more sites across the country. The information gathered in this survey will be used for planning and policy decisions that affect the health and well-being of children and youth.