Original post by racheatworldI currently do Biology AS with the aim of applying to Dentistry for 2012, and I wouldn't recommend self-teaching.
It isn't necessarily that the subject is difficult, but many people in my year mis-interpret it as being hard when in fact it just has a high workload. I just wouldn't recommend studying alone, as it may sacrifice revision for your other exams. I have the same predicted results as you (A's), and out of all of my exams, Biology is the one that I couldn't self-teach.
Mind you, if you're coping well with your current subjects and have spare time on your hands, I'd say try it, make sure you have the support of tutors in your school and possibly use any frees in college (I assume you have study-periods) to drop in some AS classes?
Good luck, as other have already said I'd take it up as an AS next year, drop your English, and do 3 Science A2s and Biology AS.