Looking casual in his 'Just Do It,' t-shirt and usual beanie cap, Zac Efron was spotted arriving at the Burbank Airport with his younger brother and some friends on Thursday morning. The "High School Musical" hunk toted his luggage from their ride to the tarmac-heading to catch a plane for some out of town sibling action over the weekend. Meanwhile, the 21-year old Disney star is also gearing that's sure be a spectacular run of premier events and promotions prior ti the October 24th release of "High School Musical 3: Senior Year." The film picks up with “Troy and Gabriella struggling with the idea of being separated from one another as college approaches. Along with the rest of the Wildcats, they stage a spring musical to address their experiences, hopes and fears about their future.”