Chlamydia is the most common STD among teens. Of the more than 1.4 million cases of Chlamydia reported in 2011 in the U.S 33 percent of those cases were reported by individuals 19 and younger.
Trichomoniasis is the most common protozoan STD in the US. Aside from giardia, which is rarely sexually transmitted, it's the only protozoan STD.
HPV
Chlamydia is the most common bacterial STD in the US, and the most common reportable STD. You should know that not all STDs are reportable, so the CDC doesn't get direct reports about HPV or trichomonas.
Babysitter
Same things they do in the US well most of the things that they do in the US
the most common language in the US is English
In the US, your religion is primarily chosen for you at birth. I wouldn't say there's one most popular religion that teens "join" though.
Only 30% of teens work in the us
The most popular sites for us teens now are facebook, oovoo, and skype
Tornadoes are most common in Texas
The most common Jacket / dress size in the US is a 6-8
Common cold