Learning the truth about the way in which children develop is not easy. It requires immense patience and the ability to make objective observations that are free from personal prejudice. This paper discussed developmentally appropriate activities and materials for the cognitive development of children in early childhood. The paper explains key terms in the topic such as developmentally appropriate materials and activities, cognitive development and children in early childhood. Other key issues in the paper includes: factors affecting early childhood development. It observes that the way children behave affect their development and learning and the knowledge of children’s developmental level in cognitive development affects the way the teacher, parent and caregivers teach their children. It therefore suggests that to ensure that children grow to their full potentials, they should be provided with opportunity for appropriate cognitive activities and materials.