But immersion proponents say parents should instead fear a bilingual education system that has been a detriment to their children's educational growth.
Ron Unz is the California millionaire funding Proposition 203. He also funded California's Proposition 227 in 1998.
In California, 95 percent of kids in bilingual ed were not moving into mainstream classrooms. "It turns out Arizona had a 97 percent failure rate [in grades K-6]," Unz says.
He calls bilingual education "a very unsuccessful program that nobody wants. It's so complicated and confusing that people haven't paid much attention to it."
In Arizona, some parents are paying attention. Shortly after California voters passed Proposition 227, Unz says, he started getting phone calls from concerned parents, calling bilingual education discriminatory and ineffective. The majority of them are Latinos, he says.
State Senator Joe Eddie Lopez, a Phoenix Democrat, is one of Unz's staunchest critics and a strong proponent of bilingual ed.
Lopez calls Unz "a racist."
"I think he's an opportunist," Lopez says. "But I would not put the same tag on Latinos pushing for the initiative. They are being misguided."
Unz calls Lopez's racist tag "very silly." He notes that it was Latino parents who also sparked California's ballot measure.
The suggestion of racism is one of several tactics being used to derail the initiative. Opponents also say it takes away parental choice and threatens language and culture.
But it's clear watching Martín and his friends, who are mainly Mexican, that they will never lose their language or heritage. If anything, they are already bicultural. Their lives function best in Spanish, yet they live the American culture.
On a recent October day, there are 75 to 100 kids knocking a few blue rubber balls around the handball courts at Carl Hayden.
Martín and his good friend Ernesto are leaning against the warm chain-link fence, eyeing a couple of semi-impressive handball matches. They've stood there all lunch hour waiting to get in a game. The bell will ring shortly, so they want to play.
They finally get some action. "Ya ganamos tres," Martín says 10 minutes later. "We already won three."
He and Ernesto exchange a "cool" handshake -- a full-finger grip followed by a light tapping of the fists. "Ándale hué!" Ernesto shouts, Spanish slang for "all right!"
Like the rubber balls, Spanish bounces off the shiny concrete walls in each of the nine courts.
Me debes tres dólares. You owe me three dollars, one kid tells another after winning three games.
Dale! Hit it!
Está bien guapa. She's pretty hot, one boy says about a girl in a yellow top.
Ya va sonar la campana. The bell's going to ring.
Carl Hayden High, near 35th Avenue and Roosevelt Street, is in the heart of a giant Latino community. It seems unlikely that Martín and his friends, surrounded by thousands of Hispanic voices, will slip away from their heritage so easily.
Martín is a slender teen with puffy black hair. He closes the spiral notebook and jumps up from the sofa to see what's frying on the stove. His little brother Julio, an extremely shy child with a cereal-bowl haircut, fills the vacancy and begins jotting down a column of multiplication tables. He is in fifth grade at William R. Sullivan School.
The middle child, Gisela, a Carl Hayden freshman, sits hunched over a black wooden desk, her brown hair draped over her left shoulder as she reviews a lengthy list of spelling words.
Like contortionists, the kids move their bodies every which way, trying to find a comfortable study position in this cramped single-wide trailer where the living room, kitchen and bathroom are just steps away from each other.
The family has little money. A quick tour of the ancient trailer they've called home for the last two years shows that.
In the trailer's center, by the front door, stands a dilapidated dining table, strips of plastic molding peeling from the edges, revealing dry glue-coated particle board. Four chairs of different colors, heights and conditions complete the ragged dinette set.
Throughout the day, Maria, Martín's mom, keeps a full pitcher of iced red aguita -- lightly sweetened Kool-Aid -- on the table.
In the kitchen, a small, white gas stove is lodged next to an aged steel sink filled with a few bean-coated dishes. The floor is covered in sticky beige linoleum. In the only bathroom, a beige porcelain sink is suspended by a thick piece of particle board that also serves as a vanity, filled with makeup canisters, shampoo, toothpaste, other toiletries. A thin white curtain conceals the contents under the sink.