Tegan & Sara find themselves back in school

"We're in a high school, so let's act like a bunch of high schoolers," Sara Quin suggested Friday from the stage of the Commerce Bank Arts Centre, the 1,500-seat theater located within Washington Township High School in Sewell.

She and her twin sister, Tegan, seemed a bit nonplussed; they were expecting to be in Philadelphia. ("Where are we? See-well?" asked Tegan.)

But that just gave the Canadians more fodder for their well-known tendency for stage patter. A large Philadelphia contingent helped fill the venue with an enthusiastic, all-ages, mostly female crowd, and while there was little overtly high-schoolish behavior, there was plenty of good-natured banter and little use of the theater's seats.

Tegan and Sara write bittersweet songs of love's travails, but cloak many of them in chipper New Wave melodies or zippy power pop, and their convivial 90-minute set drew heavily from their fifth and best album,

The Con

.

"Dark, you can't come soon enough for me," Tegan sang, and the song quickly morphed from a stark acoustic ballad to a buzzy, triple-guitar rocker. (The sisters, both of whom play guitars and keyboards, were backed by a trio of males on guitar, bass and drums.) In "Hop a Plane," Sara sang of a relationship's demise, but a rousing Clash-like riff tempered her desperation.

The twins have an admittedly sentimental streak - "We're like kittens," Sara joked - but they undercut it with humor and succinct and catchy tunes.

Tegan introduced "Soil, Soil" with a discursive story about feeling rejected and depressed, eliciting "awwhs" from the audience and mock violin-playing from her sister. (The story took longer than the two-minute, harmony-rich song.)

Sara talked of once being teased about her haircut by some Philly teens. ("It's OK: there's absolutely nothing fun about being 17," she said.)

Northern State, the New York trio of female MCs backed by tapes, samples, and a live drummer and guitarist, opened with a humorous set that crossed the Beastie Boys with Le Tigre with a profanity-laced pep rally.