It's called the winter challenge and it is sponsored by Stringing magazine the name of the challenge is "Black and White".
I had read about the challenged in the magazine last year but did not entered because I had just started beading and thought I would wait and enter this year. I had forgotten all about the contest until I read one of the posts.
Go to the topics under Stringing magazine and the topic Is "Stringing Challenge Deadlines" there you will see the web site and it will link you to the rules of the contest.
Good Luck
Roma