Zac Efron Is Light in His Flip Flops

1/9/2009 6:00 PM PST BY TMZ STAFF

Attention Target shoppers: Zac Efron is airborne in the parking lot.

The 21-year-old "High School Musical" star did research for all his upcoming teen roles by acting like a ten-year-old.

In Hollywood, it's all about staying young.