An older brother, Felipe, is a house painter who works long hours and pays for her school supplies. He has been urging her to study hard for the exam. And Alma hopes to serve as an example to her 14-year-old sister, Rosalinda.
Passing the exam is key to Alma's dreams of attending Santa Ana College to study nursing and eventually lead a more comfortable life than her parents have, she said. "You get more money" if you graduate, she said.
The stakes are high for students who don't earn a diploma. Dropouts earn $18,734 a year on average, about one-third less than high school graduates, according to the U.S. Census Bureau.
Besides her after-school tutoring and prep class on Saturdays, she practices reading comprehension, essay writing and other skills in a workbook at home at least one hour a night.
Some of her classmates say they will drop out if they don't pass this time. But Alma has vowed to keep taking the test until she succeeds.
"Sometimes, I want to give up," she said. "But then I think about my family."
Alma's mother, Elinda, 45, has a fourth-grade education and makes cakes at a bakery. Her father, Jesus, 56, completed two years of high school and works in a factory. Four years ago, they decided to move their family from a small village near the city of Apatzingan to the United States so their children would have a better future. Now, they are worried that their daughter won't graduate, and they feel helpless.
Teachers, her mother said in Spanish, "tell me she is an excellent student. But she says this test is just so hard. We are very worried. We want her to pass this test."
"She's thrown all her enthusiasm into this. We want her to progress. She's a woman and I don't want her to suffer the way I have," she said.
Ashley, a gregarious only child who gave up cheerleading to buckle down in her senior year, was one question away from passing the math portion of the test the third time she took it. Her principal at Chino Hills High School insisted on telling her personally to cushion the blow.
"I cried," she said. "It was the worst moment possible."
Principal Carl Hampton, affectionately called "Hampton" by many students, is a passionate advocate of the exit exam. But "the most heartbreaking thing you can do as a principal is telling a girl like that that she failed," he said. "I felt like it had to be me to tell her."
Ashley is among a handful of the school's 650 seniors who have yet to pass one or both parts of the exam. She is a better-than-average student, earning A's, Bs and one C this year. But math has always been her nemesis.
"It's my least favorite subject," she said. "Something just doesn't click to me."
The teen, with highlighted brown hair and dramatic eye shadow, hopes one day to work as a cosmetic artist on Hollywood movie sets. She calls the exit exam unfair, tantamount to changing the rules mid-game.
"I'm pretty upset by it," she said.
With her test prep class at school and by practicing online, she's feeling fairly confident she'll pass the math portion Wednesday.
Her parents, a car dealership owner and a nurse, are unequivocal: Failure is not an option.
"She should have passed the first time," said Bob Daigle, her father. "She just gets too involved in everything else. She's a teenager. She works and she likes to play. She doesn't focus sometimes.... She has to pass this test to graduate. [I tell her,] 'You better be at the graduation altar there on the 24th, so whatever it takes. It's imperative. Let's finish up, and down the road you go.' "
Times staff writer Jennifer Delson contributed to this report.