Cassidy Lynn Campbell said her nomination at Marina High School in Huntington Beach is an important step forward, KTLA-TV, Los Angeles reported.
"Gay people have been brought into the limelight, and it's a very touched-on subject," she said. "It's much more talked about than transgender is."
Cassidy, born Lance Campbell, said even as a child she felt she was female. She has been living as one for the past three years.
She has become something of a celebrity by blogging about her experiences online. That, she said, has been followed by bullying in cyberspace and even sometimes at her school.
The rights of transgender students became an issue in California recently when Gov. Jerry Brown signed legislation that allows them to choose whether to play for girls or boys sports teams and to use toilet facilities they feel comfortable with.