Index of German grammar exercisesk-has interrogatives,verbs,and various stuff
Grammatik-prepositions, adjectives,word order and more
German Grammar Index-helps you with verbs, nouns, and prepositions
Test your German Grammar!-lets you test your german grammar skills
grammatik zum selbstlernen-has grammar practice
LFN Grammatik auf Deutsch-helps you with suffixes, adjectives,articles,prepositions, and pronouns
Tele Deutsch Online-has audio and exercises to help with verbs
EDU2 - Level 4d-more german grammar links
German language resources and links - interactive grammar exercises
German Grammar Main Menu - nouns, pronouns, verbs, and more
Internet Handbook of German Grammar - handbook of grammar helps
German Grammar, Deutsche Grammatik - genetive, dative, and accusitive cases
German Grammar: Review & Exercises - word order, tenses, usw
Grammar/Grammatik - adjectives, gender helps, and comparisons
Sarah's Electronic German Grammar Handbook: Outline - model verbs,exeptions,and noun cases
Amtliche Regelung zur deutschen Rechtschreibung: Regeln und Wörterverzeichnis - verbs and adjectives
Quia - Class Page - German Grammar Practice - school's personal page of grammar tips
German Grammar on the Web - reference materials and exercises
Materialien für den Deutschunterricht - Grammatik - prepositions
EducETH - Deutsch - Sprache: Grammatik - verbs
Deutsch Grammatik - adjectives, nouns, and articles
Deutsch 201: Grammatik - grammar practice
Grammatik - frequently asked questions
Deutsch Grammatik - practice with cases
Inhalt - nouns, pronouns, adjectives, and verbs
http://www.grammatikdeutsch.de/ - games with grammar