Some of the world's top women snowboarders will be descending on Mammoth Mountain March 28-30 for the unofficial world championships, the Roxy Chicken Jam. The riders will be competing in slopestyle and superpipe for a piece of the $150,000 purse. Those women interested in competing can register at chickenjam.com. There will be a free outdoor concert, featuring Silversun Pickups, in the Village March 29, for non-competitors and non-riders.