A bill that would have required all California families to send their children to kindergarten failed in the state Assembly on Thursday, the latest in a string of failed attempts over the past few years to make preschool mandatory.

This law: AB 2226, The bill aimed to require the state's youngest students to attend kindergarten before the first grade. Although it's not required, 95% of students already attend kindergarten, according to the California Department of Education.

Instead, students are required to start school when they turn six, and it is up to their families to decide whether to start in kindergarten or move straight on to first grade.

The Department of Education estimates that more than 14,000 California students will not be attending kindergarten in the 2022-23 school year.

Supporters of the bill, including the Los Angeles Unified School District and the California Teachers Association, noted that kindergarten is mandatory in 19 states and Washington, D.C., and pointed to research showing that early education is important to students' long-term education.

According to data from the Los Angeles Unified School District, children who attend kindergarten tend to perform better later in elementary school.

The bill had no formal opponents but died without debate during a fast-paced budget hearing in the Senate Appropriations Committee on Thursday, where hundreds of bills were approved or rejected based on price.

A legislative analysis of the bill said it could incur “significant” costs of hundreds of millions of dollars.

“What we were looking at is the cost. Any bill that we pass and that the governor signs is likely going to have to come out of next year's budget,” Sen. Ana Caballero (D-Salinas), chair of the Appropriations Committee and who voted in favor of AB 2226 earlier this year, said after a hearing Thursday in Sacramento.

California faces a $46.8 billion budget deficit, and Gov. Gavin Newsom and lawmakers have already made billions of dollars in cuts to mitigate the problem.

Despite the lack of organized opposition, efforts to make kindergarten compulsory have failed in the past.

Governor Gavin Newsom, a proponent of early childhood education, vetoed a similar bill in 2022, calling the effort “commendable” but saying the money wasn't included in the state budget. Newsom's predecessor, former Governor Jerry Brown, also rejected the proposal, arguing that a relatively small number of families opt out of kindergarten and that they should be free to choose what's best for them.

State Assemblyman Al Muratsuchi (D-Rolling Hills Estates), who authored AB 2226, said kindergarten is an “essential component” of education that “lays the foundation” of skills like literacy and socialization.

He cited data from the California Research Agency showing Latino children are the least likely to enroll in kindergarten and raised questions about equity.

“I was disappointed but not surprised,” Muratsuchi said after Thursday's hearing. “I think more than anything this reflects our current budget deficit, but the data is clear and we need to eliminate the kindergarten disparity. We will never give up.”