Learning grammar is fun! Whenever I tell my students: "Hello, let's do some grammar today," they will pull a long face. But grammar can be fun! You don't believe me? Have a look at the following links, there are even comic strips, one is a teach yourself course and another one is really serious stuff by an Austrian university.
I teach grammar step by step, you won' be exposed to a tsunami of grammar. Here you German grammar (the worst in the world, as some say) with funny exercises and pictures! No fear!
<a class="se_link" href="http://media.uni-klu.ac.at/OpenCourseWare/Deutsch%20als%20Fremdsprache/GRAMMATIK_idt.pdf" target="_blank"><font color="#0066cc">http://media.uni-klu.ac.at/OpenCourseWare/Deutsch%20als%20Fremdsprache/GRAMMATIK_idt.pdf</font>;</a>
<a class="se_link" href="http://www.goethe.de/resources/files/pdf49/Grammatik_ueben_mit_Comics.pdf" target="_blank"><font color="#0066cc">http://www.goethe.de/resources/files/pdf49/Grammatik_ueben_mit_Comics.pdf</font>;</a>
<a class="se_link" href="http://deutsch-als-fremdsprache-grammatik.de/DaF/DaF-DaZ-Grammatik-Bausteine.pdf" target="_blank"><font color="#0066cc">http://deutsch-als-fremdsprache-grammatik.de/DaF/DaF-DaZ-Grammatik-Bausteine.pdf</font>;</a>
<a class="se_link" href="https://www.hueber.de/sixcms/media.php/36/7480-63_001_01_deutsch_kompakt.pdf" target="_blank"><font color="#0066cc">https://www.hueber.de/sixcms/media.php/36/7480-63_001_01_deutsch_kompakt.pdf</font>;</a>