German

Okay, well, my German teacher has utterly failed me and the rest of the class who are also struggling to take in his teaching methods. What he decides to teach is random and comes mainly after a time which it is needed. What I want to say is, can anyone recommend me any books or suchlike so I can brush up on my German? I've been learning for 4 years, but christ, I really need more practice. The way it's been taught feels like about 6 months to (an extreme maximum of) a year. What I really, really need practice on is grammar, I feel. Vocabulary seems to fail me quite a bit too, seeing as that's taught the least well out of the lot.

I'm planning to take German into further education as well, so... I really need to keep in practice. Any other suggestions are warmly. welcomed.

Note: I have expressed a lot of times what I feel we need more/less of in lessons to the teacher and so have my classmates.
Note 2: Sorry if my writing seemed all over the place; it's an exam week and I'm absolutely knackered.