The Snowboarding Contest is a festival in Harvest Moon DS: Grand Bazaar. It takes place on the 20th of Winter every year.
You will receive a snowboard free of charge from Felix on the 2nd of Winter in your first year to practice for the festival. There are two different courses (an advanced and beginner course), and the type of course alternates each year.
Talk to Felix at the plaza to start the competition on the 20th of Winter, and he will then let you know what course you will be snowboarding on. You can also look at the type of course in advanced by viewing your calendar. The participant with the fastest successful finishing time will be the winner.
After going down the course and getting a recorded time, it will be judged against the two other participants. You must get a time faster than 5 seconds to win for the short course, and a time faster than 6 seconds to win for the long course.
The prize for winning will always be a Sandrose, regardless of which course was used.