The rallies titled "Wake Up California!" are being held in at least 20 places around the state today, including several in the Bay Area.
The protests are organized by Educate Our State, a grassroots campaign that has developed as state legislators have proposed further cuts to public schools, which have already faced deep cuts in recent years.
California ranks in the bottom fifth of states when it comes to funding public schools and ranks last in staff-to-student ratios, according to rally organizers.
The rallies "are all to encourage legislators to balance the budget, but not on the backs of our kids," said Crystal Brown, a spokeswoman for Educate Our State.
Three different rallies are planned in San Francisco as early as 7 a.m., while large rallies are also planned in Redwood City, Burlingame and Lafayette.
For a full list of the rallies, visit the campaign's website at www.educateourstate.org.