The family asked the school for privacy so the students say word is just beginning to spread and they say the campus is in shock.
The first accident 17-year-old Hansen got into Saturday was minor, but it knocked her blue Mini Cooper sideways on Highway 280 and since her car was perpendicular to traffic and in the middle of the freeway, it sounds like she was doing what she could to get out of there.
"She had her seatbelt on and then after the original collision, she took her seatbelt off and then when the other collision occurred, she didn't have her seatbelt on," says CHP Officer Art Monteil.
She was broadsided by a Lexus SUV that officers say was going too fast.
"We basically always tell drivers to always look far ahead so they can see hazards on the roadway and therefore you have enough time to slow down and avoid the hazards," says Monteil.
Hansen is considered one of the best water polo players in the Bay Area. She plays for St. Frances High School in Mountain View. Parents and students there say the senior is a dynamic young woman with a bright future ahead of her.
School administrators held a prayer service on campus for her Monday after school. The CHP is asking for any witnesses to the crash to come forward.
"At this point we haven't filed any charges until we complete the investigation of what actually happened. We are looking for additional independent witnesses that can give us a better idea of what occurred," says Monteil.
The passenger in the Lexus was also hurt, a 72-year-old woman. She broke her sternum and some ribs. Everyone else was OK.
Investigators say they don't know why that original crash happened. They haven't been able to speak to Hansen. They say she suffered serious head trauma and that she is in a coma.