The number of children between ages two and 11 who go online totaled nearly 16 million in May 2009 and comprised 9.5% of the active internet-using universe in the US. There also has been a 63% increase since 2004 in the amount of time this group spends online, according to data from Nielsen Online.

The time spent online among children ages 2-11 increased from nearly 7 hours in May 2004 to more than 11 hours online in May 2009. Time spent among kids also outpaced the increase for the overall population, which grew 36% in the last five years, Nielsen said.

Since 2004, the number of kids online has increased 18%, with a fairly even split between boys and girls. This compares with 10% for the total active online universe. The growth of children online also outpaces the overall growth of children in the US, where kids under age 14 are projected to decrease by 1%  from 2004 to 2010, according to July projections from the US Cencus Bureau.

Boys Spend More Time; Girls Visit More Pages

Nielsen’s data reveal that boys spend more time online, but girls visit more web destinations. Boys spent 7% more time online than girls but visited an average of 397 pages; while girls viewed 9% more web pages - an average of 494 -  than boys did in May 2009.

Online video viewing among 2-11 year-olds was split evenly between boys and girls, with 5.1 million boys and 5.2 million girls viewing video online in May. However, online video consumption between boys and girls is not as even. In May 2009, boys led in viewing and time spent, consuming 61% of video streams among children and 57% of the time spent viewing videos.

In terms of most-viewed video brands, the Nielsen data also show marked differences in which sites girls and boys visit. For example, boys are heavy consumers of Pokémon and girls still love Barbie. Nearly 48% of video viewers on the Pokémon web brand were boys ages of 2-11, while 38%of video viewers on the Barbie web brand were girls ages 2-11.