LOS ANGELES — Cecelia Thornton sets up a makeshift classroom at her kitchen table every day after school to tutor her grandchildren in reading and writing with materials she buys at the local thrift store in the Mojave Desert town of Adelanto.

The 5- and 6-year-olds, she said, just aren't learning enough in their classes at Desert Trails Elementary School.

That's the key reason why she and a band of other parents and guardians filed a petition Thursday under California's "parent trigger" law to demand reforms at the K-6 school where just 35 percent of pupils last year tested proficient in reading and 46 percent in math.

If the school doesn't agree to act upon the parents' demands, ranging from cleaner bathrooms to more rigorous instruction, they're planning to start the process to convert the school into an independent charter.

"As a grandparent, I shouldn't have to be sitting at a table doing what a teacher should be doing," said Thornton, who is legal guardian for her grandchildren. "It saddens me."

Principal David Mobley received the petition, signed by about 70 percent of the parents at the school, and set up a meeting to discuss issues. "Their long-term goals are very much what we want to do," he said.

The move at Desert Trails, a 90-mile drive northeast of Los Angeles, is the second in California under a 2010 law that allow parents to demand far-reaching reforms at failing schools through a petition signed by more than half the parents at a given school.

The Desert Trails parents were inspired by the first parent trigger effort by parents at an elementary school in Compton, which failed when Compton Unified challenged the petition in court. The petition was dismissed on a technicality.

Those parents, however, succeeded in getting the first charter school approved in the city and many transferred their children there.

Desert Trails parents are hoping they'll be more successful in collaborating with district administrators to reform their school. "Either they work with us, or they let us turn it into a community charter school," said Doreen Diaz, organizer of the Desert Trails Parent Union.

Diaz, mother of a fifth-grader, said she and a handful of parents have been stymied in their efforts to reform the school for several years. "They said you can change schools," Diaz said. "That's not an option for us."

Parents have already presented a list of demands to the Mobley, including smaller class sizes, a wider curriculum including science, art, history and physical education, more classroom computers, and better maintained bathrooms.

Thornton said the bathrooms are so dirty that children do not use them. Bullying is also a problem due to the lack of playground supervision. Parents want more aides.

Mobley, who took over the school this fall, said he shares the parents' goals, but a number of them would be violations of teacher union contracts, such as basing teacher evaluations on student performance. Budget constraints may also prevent other goals such as buying high-tech whiteboards and computers.

Nevertheless, he said he will continue to meet with the parents. "The goals are similar at the end, but they want to go through a different process," he said.

The parents were directed by Parent Revolution, the Los Angeles-based nonprofit that spearheaded the parent trigger law and Compton campaign. It guided the parents on organizing tactics and petition writing, but has not led the effort, said Ben Austin, executive director.

"From beginning to end, this has been a parent-led process," he said.

The petition calls for the school to be converted to a charter. The district has 40 days to verify signatures and form a plan to meet the list of parents' demands. If parents are not satisfied with the district's response, they will move ahead on forming the charter, Diaz said.

Diaz said she was motivated to organize parents after her daughter's experience in special education classes that left her with a second-grade reading level in the fifth grade. After extra help from a support teacher, her reading level quickly progressed to a fourth-grade level.

"It makes me wonder what was she being taught all those years," Diaz said.

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