Online games for pupils:

1  mes-games.com: vocabulary and grammar games:
    topics: daily routines, animals, family, feelings, fruit, people and jobs, verbs, ...

2  a4esl.org/a/g.html: lots of basic English grammar quizzes 

3  eslgamesplus.com: sentence games, vocabulary games, drag and drop, ...

4  gamestolearnenglish.com: basic exercises (nice layout, nice games):

4.1 Fast Hands / Speed Balls: food, animals, body, clothes, letters, furniture, jobs, transport,

    sports, garden, computers, hospital, traffic, nature, colours, numbers, ...

4.2 Other games: word order, comparatives, falling clouds, hangman, memory, ...

5  British Council (!): games, stories, songs, grammar

    mention: to get the worksheets you need a login - causes no costs (britishcouncil.org)

6  marks-english-school.com/games.html: Play basketball or golf: tenses, prepositions,

    comparatives, weather, vegetables, classroom, nature, toys, ...

7  englishclub.com: vocabulary games (matching, jumbled sentences, jumbled words, hangman,

    ...), grammar games, pronunciation games.

8  englisch-hilfen.de: lots of topics, quizzes

9  funenglishgames.com: games, activities, worksheets, quizzes, videos, fun stuff

10  lots of crossword puzzles + answers (elcivics.com)

11  BBC: Quizzes, quiznet, crossword, wordmaster, beat the keeper

12 Guessing words: Create your own hangman-game: hangmanwords.com