E.L. Easton
English Online: Materials for Learning and Teaching

a4esl
Activities for ESL/EFL Students

ManyThings
Interesting Things for ESL Students

ESL Blues
ESL Blues (Pre-Intermediate to High-Intermediate English)

UVic Study Zone
University of Victoria Study Zone
From Elementary to Advanced English Level Exercises and Activities

Internet Grammar of English
The Internet Grammar of English from University College of London

Grammar & Mechanics
Purdue's OWL: Grammar & Mechanics
Handouts and exercises to help you develop your grammar and mechanics knowledge and skills

Grammar & English Usage
ESL Grammar & English Usage
Thousands of links to help you improve your grammar

ESL Vocabulary
ESL Vocabulary Thousands of links to help you improve your vocabulary knowledge

ESL Podcasts
Podcasts for ESL Learners
(Listen to news reports and read the accompanying transcripts)

ManyThings Videos
ManyThings Videos
(YouTube videos to help you improve your English)

CDL Project
California Distance Learning Project
Adult Learning Activities: Choose a topic, select a story, listen to ir or watch the video… and do the activities accompanying it!

ESL Listening
ESL Listening
Thousands of links to help you improve your listening skills

ESL Reading
Thousands of links to help you improve your reading skills.

Reading Comprehension Texts
Over 100 texts with their corresponding reading comprehension exercises!

Reading comprehension worksheets
Reading Comprehension worksheets which include original stories, poems, essays, and articles.

Reading Skills
Improve your reading skills in English at the basic, intermediate and advanced levels.

ESL Writing
ESL Writing
Thousands of links to help you improve your writing skills

ESL Speaking
ESL Speaking
Thousands of links to help you improve your speaking skills

Cambridge Advanced Learner's Dictionary and Oxford Advanced Learner's Dictionary. You can use either of these two dictionaries (or both!) as your monolingual dictionary, for the whole of your degree. If you haven't started using them, it's high time you did. These are great tools that will help you complete vocabulary assignments successfully and solve general lexical doubts. But they can also be excellent tools when working on your writing assignments for other courses, and they can even help you solve pronunciation doubts!
CEF Levels: B2 to C2 (Upper Intermediate/Advanced)

Cambridge Dictionary of American English. Use this dictionary to learn about the differences between American and British English in terms of spelling, pronunciation, and word meaning and use, mainly.
CEF Levels: B1 to B2 (Intermediate/Upper Intermediate)

Cambridge Dictionary of Idioms. An idiom is a group of words which, when used together, has a different meaning from the one which the individual words that make it have. The English language is full of idioms (more than 15.000!), and native speakers use them all the time. In a nutshell, idioms should not slip your mind if you want to communicate successfully with other speakers of English!
CEF Levels: B2 to C2 (Upper Intermediate/Advanced)

Cambridge Dictionary of Phrasal Verbs. Phrasal verbs are an integral part of the English language. If you want to make your English sound more native-like, then you no doubt need to learn phrasal verbs. Remember: you must not only know what a phrasal verbs means but also, and most importantly, you must know how to use it.
CEF Levels: B2 to C2 (Upper Intermediate/Advanced)

Merriam Webster Dictionary. Here you can find a tab for plain dictionary use, another tab for thesaurus, and another tab for Spanish-English.

Merriam Webster Learners' Dictionary. An American English dictionary and much, much more to help you enlarge your vocabulary!

Thesaurus.com. This is a super-easy-to-use online tool, which you will keep coming back to after you discover it, especially when you are writing papers for your other, non-language classes (literature, culture, etc.).

You can learn English also for fun. You may find the following links interesting for your personal interest in the English language. Here are links to idioms, slang, fun facts, famous quotations… Hope you'll enjoy them!!!

IDIOMS

DogHouse Idioms
The Dog House - Idioms

SLANG

http://www.daveseslcafe.com/slang/a.html
Dave ESL Cafe's Slang Page - Slang