"In 2005, 47 percent of high school students (6.7 million) reported having had sexual intercourse, down from 54 percent in 1991. The rate of those who reported having had sex has remained the same since 2003.
Of those who had sex during a three-month period in 2005, 63 percent -- about 9 million -- used condoms. That's up from 46 percent in 1991.
The Centers for Disease Control and Prevention said the number of births among girls in this age group dropped 38 percent from 1994 to 2002 alone, even though the number of girls 10 to 14 climbed 16 percent during the same