The woman said she did not see the boys in the street, said Sgt. Philip Wisotsky of the Danville police.
Making what Wisotsky called a "bizarre accident" even odder, the woman stopped the car after hitting the 15-year-old boys, trapping them under the Nissan Sentra.
"As she was exiting the roadway she felt the car drive over something," he said. "So she stopped the car immediately, got out and saw the two boys underneath."
The woman called 911. Firefighters from the San Ramon Valley Fire Protection District arrived on the scene, lifted the car and got the boys out, Wisotsky said.
They were taken to John Muir Medical Center in Walnut Creek and treated for minor to moderate injuries. One boy suffered a damaged spleen, punctured lung and burns on his back.
At the hospital the boys told Danville police's Traffic Officer Jason Hoschouer what had happened.
"The kids told the officer that they were stargazing and they fell asleep in the street," said the sergeant.
They had been sleeping face down, on the east side of the cul de sac, Wisotsky said.
The woman is not being charged at this time, he said. The investigation is still ongoing.