The numbers 1 to 5 in the development of children's number concepts

The structure of preschool children's number concepts was investigated. It was hypothesized that preschoolers have number concepts based on the numbers 1 to 5 rather than on the decade structure. In Experiment 1, children were taught how to solve problems using the number 5 or the number 10. Children given the former solved almost all the problems correctly. In Experiment 2, children were asked to resolve numbers into 5's and x's or to find supplements to 10. It was significantly easier and faster for children to resolve numbers than to find supplements. In Experiment 3, children were given both addition and subtraction problems. Performance in addition and subtraction was comparable. Strategies suggested that children understood numbers to 5 as a privileged anchor. These results are discussed in terms of a new model of a representational system of numbers.