A poem a day:
http://poetry.com/
Grammary Quizzes:
http://grammar.ccc.commnet.edu/grammar/quiz_list.htm
Grammar Games:
http://www.eduplace.com/cgi-bin/hme-quiz-directions.cgi?Grade=4&Unit=1&Topic=The+Sentence
Punctuation Paintball:
http://www.iknowthat.com/com/L3?Area=Paintball&COOK=