LOS ANGELES — Most of the nearly 60,000 Central American children who have arrived on the U.S.-Mexico border in the last year still don’t have lawyers to represent them in immigration court, and advocates are scrambling to train volunteer attorneys to help cope with the massive caseload.

With the number of unaccompanied immigrant children more than doubling this past fiscal year, the need for attorneys has surged, and it has been exacerbated by the immigration courts’ decision to fast-track children’s cases, holding initial hearings within a few weeks instead of months.

Immigrants can have counsel in immigration courts, but lawyers are not guaranteed or provided at government expense. Having an attorney can make a big difference: While almost half of children with attorneys were allowed to remain in the country, only 10 percent of those without representation were allowed to stay, according to an analysis of cases through June by the Transactional Records Access Clearinghouse at Syracuse University.

Efforts are underway from White Plains, New York, to New Orleans to train attorneys at private law firms on the country’s byzantine immigration laws and how to work with traumatized, Spanish-speaking children, many of whom are fleeing violence — a far cry from the corporate clients most deal with on a daily basis.

“We’re doing pretty well on finding willing lawyers. We’ve got to get them trained, we’ve got to get them matched to that child,” said Reid Trautz, director of the American Immigration Lawyers Association’s practice and professionalism center. “It just takes time.”

Last month, Vice President Joe Biden urged lawyers to increase efforts to take on the children’s cases. Since then, the cities of San Francisco and New York have each announced plans to allocate roughly $2 million to help provide more lawyers for unaccompanied minors. California has appropriated $3 million toward the effort.

About 800 immigration lawyers have signed up to volunteer on the cases, the immigration lawyers association said.

So have many other attorneys without any background in immigration law. They are being trained and paired with experienced immigration practitioners, who serve as mentors.

“We’ve had tax lawyers do this, corporate lawyers, real estate — anybody can do it,” said Ricardo Martinez-Cid, president of the Cuban American Bar Association, which started a program earlier this year to represent unaccompanied children in Miami.

Immigrant advocates say the efforts are working, but not as quickly as desired. Nonprofit organizations have been boosting staff, but there aren’t enough experienced immigration lawyers to take on the cases or to mentor volunteers. Nor is there enough long-term funding for cases that can take more than a year to resolve, they said.