Maturity level is as important as a child's age in determining readiness for school.

A child is usually big enough to use a regular seat when he or she is between 8 and 12 years old. Before allowing your child to use the regular seat and adult seat belt, make sure the seat belt fits the child. The shoulder belt should lie across the chest, not the neck or throat, says the American Academy of Pediatrics (AAP). The lap belt should lie across the thighs, not the stomach. The child should be able to sit so that his or her back is against the back of the seat and his or her feet hanging down, with the knees bent. Until your child reaches this size, he or she should remain in a booster seat.

Call your child's doctor if your child has fallen or taken a blow to the head and briefly lost consciousness. Seek emergency medical help after a fall or blow to the head if your child is unconscious; is breathing abnormally; is bleeding from the mouth, nose or ear; has pupils of unequal size; is dizzy or confused; or is vomiting.

Caffeinated beverages also may cause sleep problems in children and lead to dehydration in hot weather, because caffeine causes the body to eliminate water. Also, children who drink lots of carbonated beverages -- whether caffeinated or not -- often aren't drinking enough milk, a good source of calcium.

According to the 1999-2000 National Health and Nutrition Examination Survey (NHANES), 15 percent of children ages 6 to 19 years old were overweight. In 1976, 7 percent of children ages 6 to 11, and 5 percent of children 12 to 19 were overweight.

In the United States, the average age for a girl to start menstruating is 12. The start of menstruation -- called menarche -- cannot occur until a girl's entire reproductive system has matured.

Each state looks to the schedule of vaccines recommended by the Advisory Committee on Immunization Practices (ACIP), American Academy of Family Physicians and the Committee on Infectious Diseases of the AAP.

ADHD doesn't interfere with intellectual ability. Many ADHD kids are highly intelligent and creative.