Growing up and growing old
Biology · Key Stage 2 · The School
The stages
Human life runs through recognisable stages: baby, child, adolescent, adult, and older adult. Each has its own pattern of growth. Babies grow fastest of all — roughly tripling their weight in a year. Growth slows through childhood, speeds up again in adolescence, then stops. After that the body continues to change without growing.
Everyone on their own timetable
The stages are the same for everyone; the timing is not. Two eleven-year-olds can be a head apart in height and both be entirely typical. Growth spurts arrive at different ages, and starting earlier or later says nothing about how tall or healthy someone will end up. This is worth knowing precisely because it is the age at which people compare themselves most.
Puberty, in outline
PUBERTY is the stage when the body becomes able to reproduce. It usually begins somewhere between about eight and fourteen and takes several years. It brings a growth spurt, body hair, changes in voice and skin, and changes in mood and sleep as well as body. It happens to everyone, it is not an illness, and questions about it are for a trusted adult — a parent, a carer, a teacher or a school nurse.
Draw a line for 0 to 80 years and mark the stages. 0–2: the fastest growth of all, roughly tripling in weight. 2–10: steady growth, learning, milk teeth replaced. 11–16: puberty, a second rapid growth spurt. 18–40: full adult height, greatest physical strength. 40 onwards: gradual changes in sight, strength and bone density. Notice the two spurts, and how much longer the flat part is than either.