Children learn about number by talking and doing. This book offers closely observed accounts of what children in their early years and at primary school say and do. Some arise from classrooms; others are based on interviews and day to day interactions. Together they illuminate the learning, and therefore the teaching, of mathematics to young children.The first chapters look at early mathematical development at home and show how parents and grandparents can enhance learning. A study of a primary class responding to fractions illustrates how the children listen to each other’s ideas. A group of children considered to have challenging behaviour discuss what helps and hinders their learning as they work on a project on robots. Unofficial talk is also revealing, as the observation of children in the bottom set for mathematics demonstrates. And when working with bilingual pupils, what happens when the children teach the adult to count in their language – one the adult doesn’t know?This range of observations, research and practice will be of immense value to all primary and early years teachers and to families wishing to develop their children’s numeracy.