Stephanie Deffner, 32, was arrested on Springtown Boulevard in Livermore at about 3:40 p.m., a police spokeswoman said. Deffner was charged with one count of possession of a controlled substance and one count of being under the influence of a controlled substance, according to the spokeswoman.
Controlled substances include cocaine, heroin and prescription drugs such as codeine or hydrocodone, according to California state law.
Deffner, of Pleasanton, teaches economics and AP human geography, the study of the world, its people, communities and cultures.
She was booked into Santa Rita Jail in Dublin; she was released on $12,500 bail, according to reports.