Caught in the Act!
03/30/2011 AT 06:00 AM EDT
After taping her Good Morning America mini-performance in San Francisco, Britney Spears paid a visit to the GLBT History Museum in the Castro District, along with her boyfriend Jason Trawick. "She was very polite and attentive," a source tells us of the upbeat pop star. "She looked really good and really healthy." And when Spears left the museum after hearing all about its mission, a throng of fans was waiting for her outside.
Lady Gaga got a surprise on stage while celebrating her 25th birthday during her Monster Ball tour stop at L.A.'s Staples Center: a birthday cake. The crowd sang "Happy Birthday" to the pop star, who blew out her candles, then threw them to her screaming fans. In the audience: Kate Walsh, who arrived in a glittery, Gaga-inspired silver sequined blazer holding hands with a curly-haired gentleman.
Joe Jonas sipped on a red-colored drink while hanging out with a buddy and two female friends at the grand opening of Tru Hollywood, a new L.A. nightclub.
By REAGAN ALEXANDER, VANESSA DIAZ and DAHVI SHIRA