CPV code 85311300 designates Welfare services for children and young people in the Common Procurement Vocabulary (CPV 2008), the EU classification used to describe the subject of public contracts.
85311300 is a leaf code — the most specific level of its branch — so it can be used directly as the main CPV code of a contract notice. If it does not quite fit, check the neighbouring codes under 85311000 (Social work services with accommodation).