Sushi Test - This is mainly aimed for high school students. Students can take a beginners test covering grammar, vocabulary, kanji, and listening.
Digital Dialects - This site offers a variety of resources (numbers, phrases and greetings, vocabulary, kanji, etc).
Grammar
Jgram
Tae Kim's Guide to Japanese Grammar
Kanji
Reviewing the Kanji
On'Yomi vs Kun'Yomi
Vocabulary
Manythings
ELanguageSchool
Dictionaries
Denshi Jisho
Jim Breen
Digital Dialects - This site offers a variety of resources (numbers, phrases and greetings, vocabulary, kanji, etc).
Grammar
Jgram
Tae Kim's Guide to Japanese Grammar
Kanji
Reviewing the Kanji
On'Yomi vs Kun'Yomi
Vocabulary
Manythings
ELanguageSchool
Dictionaries
Denshi Jisho
Jim Breen