<p>I was just searching online for some online (or printable) practice AP exams, particularly for biology, and I came across SparkNotes' Test Prep Center (which I did not even know they had). They have a 50-question AP Biology exam with a nice variety of questions, and they provide an awesome feedback report telling you how you did in each area. You can review the entire test and read explanations for every single question. They have exams for other subjects, too.</p>
<p>Just thought I'd share, since to me, this is now a valuable resource. </p>
<p>Here's the page from which you can select your subject: SparkNotes</a> Test Prep: Advanced Placement Tests Information Center</p>