Pearl Jam, R.E.M., Dave Matthews, and others joined Neil Young & Crazy Horse this weekend (Oct. 20-21) outside San Francisco for the 15th annual Bridge School Benefit concerts. The largely acousti

Pearl Jam, R.E.M., Dave Matthews, and others joined Neil Young & Crazy Horse this weekend (Oct. 20-21) outside San Francisco for the 15th annual Bridge School Benefit concerts. The largely acoustic concerts at Shoreline Amphitheatre featured two new songs and the live debut of two others from Pearl Jam, and wrapped both nights with Young and Crazy Horse's audience participation-aided cover of John Lennon's "Imagine."

At both shows, the first music of the day came from Young, who, with his wife Pegi, founded the Bridge School as a learning facility for physically challenged and severely speech-impaired children. Under clear blue skies, the artist gently strummed out "Sugar Mountain" and Bob Dylan's "Blowin' in the Wind" on his own before introducing singer/songwriter Jill Sobule. The latter's sets were highlighted by her own "I Kissed A Girl" and a cover of Destiny's Child's recent hit "Survivor."

Ben Harper, playing without his band the Innocent Criminals, concentrated on subdued numbers such as "I Shall Not Walk Alone," the new song "When She Believes," and his familiar cover of Marvin Gaye's "Sexual Healing." On Sunday, he closed his set by bringing his mother onstage to sing and play guitar with him on Dylan's "Tomorrow Is a Long Time."

Although a seemingly peculiar choice for this type of show, '80s rock veteran Billy Idol got the crowd up and moving both nights with a string of hits such as "Cradle of Love," "Eyes Without a Face," "White Wedding," and the powerful "Rebel Yell." On Sunday, Young guested on guitar and vocals for a run through Buffalo Springfield's "For What It's Worth."

Singer/songwriter Tracy Chapman's somewhat depressing sets featured familiar cuts such as "Mountain O' Things," "Fast Car," "Baby Can I Hold You," and the more cheery "Give Me One Reason," which found the crowd chipping in on harmony vocals at the artist's request. Chapman also covered Ben E. King's "Stand By Me."

R.E.M. focused mainly on songs from its past two studio albums, opening on Saturday with the recent singles "Imitation of Life" and "All the Way to Reno," from the new Warner Bros. album, "Reveal." Both nights included more groove-oriented takes on "Let Me In," frontman Michael Stipe's elegy to the late Kurt Cobain. The group also offered crowd pleasers such as "Man on the Moon," "Find the River," "The One I Love," "Everybody Hurts," and "Losing My Religion."

On Saturday, Dave Matthews repeatedly expressed his trepidation at playing solo in front of such a large crowd, but any nervousness was not apparent during his set either night. Highlights included the title track from his band's latest RCA album, "Everyday," the unreleased chestnuts "Grace Is Gone" and "Bartender," a brand new song featuring the lyric "where you are is where I belong," and, on Sunday, a duet with Chapman on Daniel Lanois' "The Maker."

Pearl Jam was making its fifth Bridge School appearance, and as has become custom, took the opportunity to feature new and rare material. One new song, "Last Soldier," featured a simple melody not unlike those purveyed by Young or R.E.M., while a second, "I Am Mine," was marked by frontman Eddie Vedder's reassuring lyrics: "there's no need to hide / we're safe tonight." The band also dusted off "Low Light" and the 1999 fan club Christmas single track "Drifting" for the first time in a live setting.

Crowd favorites such as "Elderly Woman Behind the Counter in a Small Town," "Daughter," and "Better Man" gave way on both nights to a cover of John Lennon's "Gimme Some Truth" and a solemn rendition of "Indifference," with Harper joining in on vocals. Both nights concluded with covers ("Last Kiss" on Saturday, "Soldier of Love" on Sunday) dedicated to the Bridge School students seated on a riser behind the bands.

Young and Crazy Horse's sets, the closers on both nights, jumped from the familiar ("Long May You Run") to the obscure ("Mideast Vacation," from 1987's "Life" album), as well as a reprise of "Blowin' in the Wind." In another nod to the Beatles, the band tackled "All You Need Is Love," which soundtracked a short highlight film of past Bridge School concerts that was played both days.

For "Imagine," which Young performed during the "America: A Tribute to Heroes" telecast last month, the band strummed out the instrumental backing while the crowd sang along at full volume.