Midterm evaluation of longitudinal study conducted through the Tayari Early Childhood Development and Education Programme. Tayari is an intervention implemented by the Kenyan Ministry of Education and four counties, with technical support from RTI International and funding from the Children’s Investment Fund Foundation (CIFF). Tayari is focused on designing, piloting and testing the cost effectiveness of investments to increase school readiness for children in Early Childhood Development and Education (ECDE) centres in Uasin Gishu, Siaya, Laikipia and Nairobi counties.