“Day of the Teacher” arose out of legislation co-sponsored by CTA and the Association of Mexican American Educators. Sen. Joseph Montoya wrote the bill and it was adopted in 1982. California has patterned its celebration after the traditional “El Dia del Maestro” festivities observed in Mexico and other Latin American countries.
"...An educated citizenry serves as the very foundation of our democracy... Today’s teachers mold the minds and train the workforce of the future... No other profession touches as many persons with such a lasting effect... Good teaching grows in value and pays dividends far beyond the classroom... California long ago recognized the immeasurable value of our teachers and has designated the second Wednesday in May to be Day of the Teacher, a special observance that honors teachers and the teaching profession... Day of the Teacher has been sponsored by the California Teacher’s Association, the Parent Teacher Association, the California Federation of Teachers, the Association of California School Administrators, the California School Boards Association, the California Association of School Business Officials, School Services of California, and the Association of Mexican American Educators and was first recognized in 1982... California has patterned its celebration after the traditional “El Dia del Maestro” festivities observed in Mexico and other Latin American countries... Day of the Teacher should be a day for school districts, parents, public officials, and the community to recognize the dedication and commitment of teachers who are educating our children..." (Assembly Concurrent Resolution No. 104 (May 12, 2004), CHAPTER 60 - Relative to the Day of the Teacher)
Source: ca.gov
In 2025 Day of the Teacher in California in USA falls on May 14.