As most sporting games go, there really is no storyline in Shaun White Snowboarding, but...

The closest thing to a storyline in this game is a very short movie file where Shaun White challenges you to go for your dream and tackle the mountain. You start out as a rookie but as you complete events you earn points that can be spend on raising your stats or by purchasing new snowboards for you to use. Complete all events and you "win" but that's about how deep the storyline is.