Here are some links to websites that I think are good for students who want to learn English. Most of these websites should be free.
British Council – Start learning English immediately.
rong-chang – This website has been online for a very long time. It’s good for beginning level students.
Voice of America – Sponsored by the U.S. government, this free website provides free English lessons, and you can learn about the United States history and government at the same time.
Learn American English Online – This is my old website. I don’t own it or contribute to it any more, but you might find some useful content here.