What happens at each age in the book The Giver?

At birth, Newchildren are cared for at the Nurturing Center until the first December Ceremonies.  At that time, they are considered to be Ones, no matter when during the year they were born.  At the Ceremony of the Ones, each Newchild is given a name and placed in a family unit, taking the comfort object which was assigned when he or she was born.

Not much detail is given in the book about what happens to children between the ages of Two to Seven.  It appears that the children grow up much like children do in our society during those years, except that everything is very regimented and done on a community level.  The girls wear their hair in braids with ribbons, and the children go to school and engage in recreation.  At age Eight, the children's comfort object is taken away, and they receive jackets with pockets, indicating that they are mature enough now to keep track of their own belongings.  The Eights also begin their volunteer hours; they are allowed to choose where they do their hours, and must have completed all the required service by the time they are Twelve.

At age Nine, the children each receive a bicycle of their own, and at Ten their hair is cut, the females losing their braids and the boys having their hair trimmed so that their ears are exposed.  At Eleven girls receive different undergarments for their changing bodies, and boys get longer trousers with a special pocket for the calculators they will begin to use in school.  Finally, at age Twelve, each child in the community will receive an assignment to a job for which they will begin training and at which they will work for the rest of their lives.