Lower-Intermediate and Intermediate Level

General 

http://www.eslgold.com/levels/low_inter.html

Grammar

http://www.esl-lounge.com/student/grammar-exercises-intermediate.php

Lower Intermediate  Grammar, Vocabulary and Pronunciation

https://elt.oup.com/student/englishfile/intermediate3/?cc=gb&selLanguage=en

Intermediate Grammar, Vocabulary and Pronunciation

https://elt.oup.com/student/englishfile/intplus3/?cc=gb&selLanguage=en

Vocabulary - Idioms Exercises

http://www.myenglishpages.com/site_php_files/vocabulary-lesson-idioms-alphabetical-order.php

Vocabulary Interactive Games (Antonyms, Synonyms etc)

http://www.vocabulary.co.il/antonyms/

Crosswords Vocabulary

http://a4esl.org/a/c3.html

Phrasal Verbs

http://www.stickyball.net/esl-phrasal-verbs.html?id=435

Idioms

http://www.stickyball.net/esl-idioms-worksheets.html

Reading Comprehension Exercises

http://www.eslgold.com/reading/interesting_articles.html

Reading

http://eslreadinglessons.com/

Audio Memory Games 

http://www.eslgamesworld.com/members/games/levels/high/index.html

Listening – Lower Intermediate 

http://www.agendaweb.org/listening/intermediate.html

Listening

http://www.bbc.co.uk/worldservice/learningenglish/general/

Listening - Intermediate

http://www.agendaweb.org/listening/intermediate.html