I heard about it on 94.9FM - a skateboarding / photography event ("phoSKATEto") in Oceanside. The sponsoring photo store would be lending out pro equipment for us aspiring amateurs to try out, for free. The subject matter was provided - a host of mostly teenaged skateboarding experts and one bike guy, featured above. There were three 90 degree arc ramps and smaller benches and ramps and beams, which I'm sure have specific names. It took a while to get a sense of rhythm for the movement, to learn the timing for the best shots. Also took a plucking of courage to stake out a spot right next to the ramps, or in the case of this photo, between ramps. The skaters were pretty skilled, and there were no collisions, with each other, photographers or onlookers.
On a side note, I'd always wondered why the soles of some sneaker-like shoes have designs on them. I mean, what's the point? Well, now I know! The majority of my shots of airborne skaters included a clear view of the bottoms of shoes.