Vocabulary

• E-Vocabulary (free)
• Quizlet (free, with upgrade options)
• Macmillan Dictionary (free)
• Vocabulary Profiling
  • English Profile (free, joint effort of many leading institutions, attributes vocabulary items to CEFR levels, different attributions for different semantic uses of a word, offers learner corpus examples for appropriate use on a particular level)
  • The Oxford Text Checker (free, based on Oxford 3000 word list & academic word list)
  • VocabKitchen (free, based on open source wordlists & open dictionary resources)

Grammar & Vocabulary

• BBC Grammar Challenge superseded by 6 Minute Grammar series
  (podcasts & interactive exercises, free but no longer updated)
• BBC 6 Minute Grammar series
  (podcasts & worksheets, free)
• MyGrammarLab
  (Pearson-Longman, access keys included in textbooks)
• www.oxfordenglishtesting.com
  (Oxford University Press, access keys included in various textbooks, additional licenses can be bought online)
• www.business-english-online.com
  (commercial, Swiss-based exam preparation website with  a limited number of free demo exercises and a reasonably priced writing correction service)
• englisch-hilfen.de
  (vastly improved layout, less advertisements, good exercises up to intermediate level, explanations in German and English)
• linguapress.com
  (concise grammar page, plenty of examples, free)
• esl-lounge.com
  (too many advertisements in free version but provides good materials for higher levels and Cambridge Exams preparation)
• Grammar Profiling
  • English Profile (free, joint effort of many leading institutions, attributes use of/knowledge about grammatical constructions to CEFR levels, offers learner corpus examples for appropriate use on a particular level)

Writing

• Tim Johns Kibbitzers (34 revision topics)
  (corpus-informed, bite-sized chunks, focus: academic writing, free)

Classroom-friendly corpus-linguistic resources (lexico-grammatical patterns)

• ForBetterEnglish (online, free, superseded by SkELL)
• Just the word (online, free)
• Netspeak (online, free)
• SkELL – SketchEngine for English Language Learning (online, free, ad free for sketchengine subscribers)

Authoring Tools

• LanguageTool – style & grammar check  (open source, free)
• LingleOnline – automated materials creation (€40.-/year – Summer 2014: service closed)
• VIEW – Visual Input Enhancement of the Web (free) – Screenshots
• English Profile (free, check CEFR level suitability of Vocabulary/Grammar, for other profiling tools see relevant sections above)
• e-tutorium.net – create interactive e-tutorials (free)