Boston’s best public school doesn’t look like the rest of the city. Overall, blacks and Latinos make up around 75 percent of students at Boston public schools. But at Boston Latin, they’re about 20 percent of the student body.

Civil rights lawyers have said the current admissions policy likely violates state and federal law, but Boston school officials say changing the admissions process is not on the table.

”I don’t think that’s the appropriate thing for us to be looking at right now,” said Michael O’Neill, chairman of the Boston School Committee.

Instead, O’Neill says officials are considering making smaller changes to help Boston public school students compete against kids coming from private schools.

You might wonder why the district doesn’t just use affirmative action practices common at universities. About 20 years ago, a federal court banned Boston from using quotas and limited its ability to use race to diversify Boston Latin.

So now, getting in boils down to two equal factors: An entrance exam and grade point average.

The Independent Schools Entrance Exam, or ISEE, is like the SAT, but students take it in sixth grade. Most students apply for Boston Latin in sixth grade and enter in seventh. Boston has offered a crash course for the last several years, at first on a first-come-first-serve basis.

“But what we found was that was mainly very engaged parents who signed up their students,” O’Neill said.

So, two years ago, the district added seats, and asked teachers at underrepresented schools to nominate their best students for the program. That has helped to bring more Latino and black students into the prep course.

Students in this summer’s course are all going into sixth grade.They said they’re learning a lot of new material. Jacob, 11, from Mattapan, says he’s learning algebra and converting fractions into percentages.

“I’m finding it a little bit difficult and, at the same time, I’m finding some of it easy,” says Jacob.

Amaya, 11, says she has been learning Algebra. Before now, she adds, “the hardest math I’ve done is three times multiplications.”

Both Amaya and Jacob are black, from Mattapan, and attend schools that send few students to Latin.

It’s not surprising that the material is new to them. The test covers subjects most sixth grade students in Boston public schools haven’t learned yet. That worries Matt Cregor, the education project director for the Lawyers’ Committee for Civil Rights and Economic Justice.

“There’s much more we have to do to prepare our students so they can succeed,” Cregor says.

He says the short prep course is a good step, but it's not enough.

“If you’re traveling to a foreign country,” he says, “it matters a lot more if you’re learning a foreign language over four or five years, rather than four or five weeks.”

 Boston has added another prep course this fall.  Boston school officials say they plan to keep using the exam to judge students applying to Boston Latin.

The other part of getting in to Boston Latin is a good grade point average.

A new Boston public schools report obtained by WGBH raises questions about kids entering Boston Latin School from private schools, especially Holy Name Parish School.

Last year the Catholic school in West Roxbury sent more students to Latin than any other private school, according to Boston public schools. Out of a class of 405, 43 — or 10 percent — of students came from Holy Name. Those 43 students make up the majority of the graduating class at Holy Name, which last year totaled 51 students.

And here’s the remarkable thing about Holy Name students: They get really good grades.

Sixty-nine percent of the students applying from Holy Name last year had A plus averages, according to the Exam School Enrollment Data Group report.

Compare that to the students applying from public schools with the best track records of getting into Latin. Only 22 percent of those students had those kinds of grades.

“What we fear is there is grade inflation [in] place here,” Cregor says.

“We reject that outright,” says Terry Donilon, spokesman for the Archdiocese of Boston.

“The kids are getting in. They’re doing really well. They’re staying. We have a high retention rate," Donilon says. "If they weren’t qualified to get in, they wouldn’t be able to succeed there.”

Boston officials haven’t suggested to us that anyone is inflating grades. Instead, they point to the unconventional grading system used in Boston.

Boston public schools grade on a one through four grading scale.  Four is the highest. To get a four, you have to show you’re close to one year ahead of your grade.

 “Other schools in Boston grade on an ABCD system. With A plus, A minus,” O’Neill says.

So the question for O’Neill is, if some kids in private schools and Boston public schools are doing the same level work, are they getting a comparable grade?

“And our suspicion is,” O’Neill says, “that because of the disparity in the two types of grading … BPS students are disadvantaged when it comes to the GPA.”

 The district is considering going back to using the ABCD grading system, O’Neill says.

 Cregor says that may help some kids, but it won’t fix the problem.

“If the district were to expand the way we look at admissions and consider additional factors beyond grades and exams, they could have a far more diverse and representative student body at each of the exam schools,” Cregor says.

Cregor and a group of other attorneys, including the ACLU of Massachusetts, have suggested ways to change the admissions process that don’t use race. One option could be setting aside a number of seats at each exam school for students already attending Boston public schools, or giving weight to students who attend under-performing schools.

They’ve warned school officials that the current admissions process likely violates federal and state laws because it disproportionately affects minority students. And they’re waging a public campaign to force change.

School committee chairman Michael O’Neill says it’s not time to change the way kids get into Boston Latin, but they are looking for ways to “level the playing field” for Boston public school students.

“It’s not giving anyone a leg up,” O’Neill says. “Everyone who goes to our exam schools are city of Boston residents. And they have a right to go, whether they have been at private, parochial or charter schools beforehand. But it’s making sure Boston public schools students have equal opportunity.”

Students return to Boston Latin this week, and the school will get its first black headmaster. There’s hope she may help the school become more hospitable for minority students. But how to get more black and Latino students to go there in the first place may take longer to figure out.

WGBH News’ coverage of K-12 education is made possible with support from the  Nellie Mae Education Foundation.