With each year, the giant outdoor music festival held in Chicago’s scenic Grant Park has continually outdone itself, bringing together the Gagas and the Green Days of yesterday and today. Complete with two headlining stages at the northernmost and southernmost ends of the park, the festival also has four lesser stages, a separate kids’ stage and the perennial Perry’s tent, where DJs spin from the moment the festival opens until the end of the night.

Surrounded on all sides by Chicago’s looming, picturesque skyline, T-shirt vendors and religious crazies (whose “Rock and roll will damn your soul” placard almost made the weekend all on its own), the festival boasts three days of music from hundreds of performers, local food vendors, non-profit and political advocacy groups, quirky sponsors and plenty of free water and accessible restroom facilities throughout the park.

It seems like the stages and the stories get bigger and better every year — if the first two days of Lollapalooza are any indication for the future of grand-scale outdoor music festivals, I like where we’re headed.

Friday afternoons at Lolla are typically worse attended than the rest of the weekend, no thanks to the demands of the working week and the Man’s efforts to keep us all down. Unfortunate, then, that hip-hop heatseeker B.o.B. was doomed to one of the earliest slots in the day — a brutal 11:30 a.m. post at one of the festival’s larger stages.

An early highlight was Mavis Staples, the legendary soul singer of Staples Singers fame who recently teamed up with Jeff Tweedy (from “The Wilco Band!” as Staples introduced him) to write and record a new album of gospel-tinged soul. Tweedy appeared onstage twice, softly strumming an acoustic guitar stage right as the 71-year-old Mavis let loose on classics ranging from “I’ll Take You There” to The Band’s “The Weight.”

On the other side of the festival, The Walkmen had just finished a set of raw, garage-rocking Britpop led by Hamilton Leithauser’s signature throat-tearing drawl. New tracks from the band’s upcoming album, Lisbon, were well received, and older tracks like “In The New Year” sounded almost like modern classics.

At Perry’s, Stones Throw Records founder and artist Peanut Butter Wolf (aka Chris Manak) was spinning a set of hip-hop classics, ranging from Snoop and the Beastie Boys to Wu-Tang and MF Doom. Deftly scratching and mashing the records and accompanying video simultaneously, Manak brought some tasteful old-school flavor to the rave-ready crowd.

Then there was Devo. Emerging in silver space-age costumes, the band played tracks from its new album before breaking into the New Wave classics and donning those signature Energy Domes, now in turquoise. Frontman Mark Mothersbaugh was as undeniable as ever, his nerdy charisma unflappable.

Back on the northern side of the festival, Dirty Projectors was creating its own brand of musical geekery, rooted instead in complex polyrhythms, melodies, arrangements and lyrics about Gatorade. One of the strongest and most hypnotic performances of the weekend, the Brooklyn six-piece played a pitch-perfect set, with lead singers Dave Longstreth and Amber Coffman stretching their ranges with shiver-inducing results.

Headliner Lady Gaga, who spared no expense in creating the “Monster Ball” of her current tour, emerged to tens of thousands of screaming teenagers and 20-somethings on a stage that looked more like a Broadway production of “Rent” than a pop music performance. But Gaga will be Gaga, and by the time she had overdramatized her way through bouts of musical theater and motivational speaking, it was clear that, apart from the dance-crazed diehards, many left disappointed and confused.

Those who did leave Gaga early (or were wise enough to not go at all) were treated to a historical performance by newly reunited NYC heroes The Strokes.