Typically, children can start kindergarten at age four or five, though the cutoff dates will vary by state. As to whether it's appropriate for your child start, that depends on their maturity, and to a lesser degree, their academic skills. There's a great deal of debate about what makes a child ready for kindergarten. Some of the factors thought to be important include the ability to deal with new situations, take care of bodily needs, form relationships with classmates and teachers, control his or her impulses, recognize and express feelings verbally, and to engage in playtime activities. Some kindergartens use 'readiness tests' or 'screenings' to determine if a child might be ready to start. However, these tests can be unreliable, with up to 50 percent margin of error. They're not very good indications of readiness, because they only show what a child's like on a given day, not how well they'll do in school. Instead, it's better to consider a range of information, like your child's birthdate, the pediatrician's observations, the preschool teacher's recommendation, and your own experience as parents. The child's socialization skills are another important indicator; so watch to see how they get along with others.