The Governors Highway Safety Association said 107 16-year-olds were killed, up 24 percent from 86 in the first six months of 2011. The increase was smaller for 17-year-olds, rising 15 percent from 116 to 133. The overall increase was 19 percent.
Allan Williams, a former researcher for the Insurance Institute for Highway Safety, said the rate of teenage fatalities remains low compared to what it was a few years ago.
Many states have adopted graduated driver licensing laws that limit young drivers to daylight hours and bar them from carrying a lot of passengers.
"Based on 2011 final data and the early look at 2012, it appears that we are headed the wrong direction when it comes to deaths of 16- and 17-year-old drivers," Williams said.
He suggested the effect of the laws has leveled off. An improving economy may also have allowed more teenagers to get behind the wheel.
Williams found increased fatalities in 25 states and fewer in 17. Eight states and the District of Columbia had no significant change.