At age 4, nearly 3 in 10 are said to be very restless and fidgety, and nearly 1 in 4, to have a short attention span. Nearly 1 in 8 is reported to be in less than very good health. About 1 in 13 speak in a way that is not understandable to a stranger or have a stutter or stammer. For example, the percentage of preschoolers reported to write their own names more than triples between ages 3 and 4, while the percentage recognizing most letters more than doubles. Other accomplishments show more moderate age differences.
Developmental difficulties show much smaller changes across ages, and some show no change.
More girls than boys demonstrate each of the literacy and small motor skills covered in the survey, and more boys than girls exhibit signs of physical activity-attention difficulties or speech difficulties. Though differences by sex are widespread, they are not large. Controlling for related risk factors such as a mother with limited education and minority-language status reduces these ethnic differences but does not eliminate them. Black preschoolers show fewer signs of emerging literacy and less good health than white preschoolers. However, racial differences are wholly accounted for by related risk factors such as low maternal education, poverty, and single parenthood.