Self Studying AP Statistics Easy or Hard?

<p>I am sophomore and this year I am taking H English, APUSH, H Chemistry, H Pre-calc, and Drama and was thinking about self studying for the AP Statistics Exam since my school doesn't allow me to take it as till junior year even though I completed H Algebra 2. I have heard a lot about how it is easy to self study Stats and about how people got 5s self studying or 3s studying the course just 2 weeks before (especially on CC), but when I look at the data only 12% of the people who take it get 5s and the average is 2.8. How come the average is so low? Is it really that easy? I can learn the material but is there any thing else I need to do? I was planning on studying for the exam using a college Stats book? Is that okay to use? Is there any other prep books I should get? I would like to get Stats out of the way since I only have one AP and will be taking 4 next year. Thank you very much!</p>