State Attorney General Kamala Harris is asking private law firms to provide free legal help to the wave of Central American children pouring into the state.

Harris has called for a sit-down Wednesday in her San Francisco office with attorneys from a dozen firms, as well as with representatives of nonprofits, legal-aid groups and charities.

The idea is to find private sources to help the children in their deportation hearings in Northern California, similar to an effort under way in Southern California.

“This is a humanitarian crisis of children fleeing extreme violence,” said Harris spokesman David Beltran. “This group will work to ensure these children receive due process under existing immigration laws.”

Beltran said the attorney general’s office itself is legally barred from representing the youngsters, so Harris is using her “convening power” to pull together private help.

The exact number of unaccompanied children showing up at the California border is hard to come by, but we’re told that the federal immigration courts in San Francisco are handling 80 cases a day involving youngsters.

Officials tell us that nine out of 10 children who appear at immigration hearings without a lawyer are sent home – while only about half of those who have an attorney are deported.

Tens of thousands of refugees and asylum seekers from El Salvador, Guatemala and Honduras have entered the country since October, and about 3,000 of them have been placed with sponsors in California. Schools in both San Francisco and Oakland have reported a surge in enrollment of immigrant children who arrived here unaccompanied.

Wall comes down: Just two months after voters overwhelmingly said “no wall on the waterfront,” developers of a proposed $100 million housing and office development at Pier 70 have scored the key endorsement of the Sierra Club in their bid to exceed height limits in the area.

Proposition F, which goes before voters in November, would allow Forest City Enterprises to double the height limit for buildings in its project to 90 feet. That’s still far below the 230 feet that Forest City first proposed.

Of course, that proposal was on the table before voters rebelled against plans for high-end condos at 8 Washington and the Golden State Warriors‘ proposed waterfront arena. In June, they passed Proposition B, giving themselves the last word on waterfront high-rise proposals.

Forest City promptly scaled back the towers at Pier 70, increased the proportion of housing units classified as “affordable” to 30 percent and guaranteed a waterfront walkway.

The company also brought on political consultant Jim Stearns, who worked with the “no wall” forces, and held meeting after meeting in the community. Eventually, it won over many of the key figures in the waterfront fight, including former Mayor Art Agnos.

Now the Sierra Club has climbed aboard, which is going to look very nice on pro-Prop. F flyers.

“We will be following the project through the rest of the permitting process,” said local Sierra Club Chairwoman Becky Evans. “But it looks like a good idea at this point.”

Foreign policy: UC Berkeley may be headed for a milestone, with campus officials predicting that a record 23 percent of undergraduates this fall will be from outside California.

The figure is even higher for the freshman class, with an estimated 30 percent expected to come from either out of state or other countries – mainly China, South Korea, India, Singapore and Canada.

Out-of-state and international students are an attractive commodity for UC, because they pay $22,878 annually on top of the in-state tuition of $12,972.

UC Berkeley spokeswoman Janet Gilmore said the increase in out-of-state students doesn’t affect in-state admissions. She says in-state enrollment is a set figure, based on state funding – or lack of it.

This way, at least UC gets some money.

Brown’s bucks: Former mayor and current Chronicle columnist Willie Brown is being paid $100,000 to represent developers in their fight to roll back the special tax assessment for the new downtown Transbay Transit Center, according filings with the city Ethics Commission.

Boston Properties and a half-dozen other developers are paying Brown to try to cut the estimated $1.4 billion assessment they’re being asked to pay on the project, thanks to skyrocketing property values.

It should be an interesting fight – because so far, Brown’s friend Mayor Ed Lee is telling folks that a deal is a deal, and he has no plans to back down.

San Francisco Chronicle columnists Phillip Matier and Andrew Ross appear Sundays, Mondays and Wednesdays. Matier can be seen on the KPIX TV morning and evening news. He can also be heard on KCBS radio Monday through Friday at 7:50 a.m. and 5:50 p.m. Got a tip? Call (415) 777-8815, or e-mail matierandross@sfchronicle.com.