Here are some websites that will help both students and teachers of ESL/EFL/TESOL:
Ask the English Teacher
http://crofsblogs.typepad.com/english/
This is the best I've seen yet. It's set up in the form of a blog, but students are encouraged to email this teacher with their questions. The posts are responses to emails.
Dave's ESL Cafe
http://www.eslcafe.com/
Click on Stuff for Teachers or Stuff for Students for oodles of wonderful help.
Activities for ESL/EFL Students
http://a4esl.org/
There are all kinds of excellent help here, and in an amazing array of languages/English.
ESL Self-study Materials
http://owl.english.purdue.edu/handouts/esl/eslself.html
Click on the different links for a list of print, audio, and computer software materials.
Interesting Things for ESL/EFL Students
http://www.manythings.org/
Many, many good links here!
ESL CyberListening Lab
http://www.esl-lab.com/
Excellent topics for gaining help and experience with verbal English.
How to Write an Essay
http://esl.about.com/cs/writing/ht/ht_essay.htm
Really good ideas here for ESL and English students as they learn to write essays.
English Idioms, Idiomatic Expressions
http://www.learn-english-today.com/idioms/idioms_proverbs.html
Common Mistakes
http://www.common-mistakes.net/
Learning English and refining vocabulary - learning from others' mistakes.
English Vocabulary
http://www.theenglishvocabulary.com/categorytopic.php?lang=3
Grouped by categories
provide examples of successful practices of pnonics for English Language Learners and building language development toward fluency
2 answers
One more website for all purposes ESL!!
Stickyball
http://stickyball.net/
Stickyball
http://stickyball.net/