Eden Palmer was identified by the San Mateo County Coroner's Office as the victim killed Saturday.
Her 14-year-old son was also in the car and suffered major injuries, the California Highway Patrol said.
Authorities said 24-year-old Constellatia Martin, 24, was driving her sedan northbound in the southbound lanes. A LinkedIn profile matching her name and age indicates that she is a computer science teacher.
CHP officers said after the crash she stripped her clothes off and tried to get into other cars.
"Just the fact the suspect was nude was a little odd to begin with. However, the suspect was detained, and we continued focusing on the crash," said Officer Art Montiel.
Martin suffered a fractured wrist and was transported to Stanford Hospital.
Authorities are waiting for toxicology reports.
"At this point, we don't know how this person entered the freeway. We are looking for witnesses that may have seen the vehicle enter the wrong way," said Montiel.
Friends of Palmer described her as a talented marketing consultant and a loving mother. They are rallying support for her son who remains at Lucille Packard Children's Hospital.
Anyone with information on the case should contact CHP. A GoFundMe for the family can be found here.