if u enjoy it then keep it. i myself enjoy biology alot, everything is fairly easy to understand- just alot to remember!
yeah my teacher is a b**ch, she cant teach to save her life, so i just bludge in class and teach myself at home....
it depends on u if u want to drop (but if u already starte yr 12 work, then i would think its too late to drop).
dont get put off bio jus coz of ur teacher... cant u go c ur science co-ordinator n ask him/her to put u into another bio class (if there is any)?