I am 2/3 thirds of sams teach yourself java in 21 days and I would like to know what to do to get proficient with programming. I heard I should look at source code, if so where can I find some. What kind of projects should I do. Should I join a part time team(by the way I am only 15 and so I am in full time education and don't have too much spare time). Join open sauce projects.
If anyone can help me as a way to improve, I would be very greatful.