Tbh mate,and this may sound a little harsh,but you mentioned that a childminder picks her up from school everyday which suggests to me you both work full time?I think you may find that this is the problem,your probably not doing a lot wrong but she may be getting wound up by other kids saying shit like "your parents don't love you,cos they never get you from school"etc.you know what kids are like,there's plenty on here!!It might be worth you both taking a day off work one day and both turn up to get her,I bet she'll be landed.think about what she's doing,all things that she knows will get attention,YOUR attention!!Some kids paint pictures and make you pretty things but your princess is probably a bit too bright for that and knows by hurting/breaking things she gets the desired effect far quicker.things like biting the child minders kid,perhaps so the child minder would refuse to get her,therefore mummy and daddy or even granny or grandpa would have to come and pick her up then,see where I'm going?The world has changed so much since I was a kid,I used to hate my mother coming to get me from school,couldn't think of anything worse,but nowadays I even see kids being picked up from comp!!!I'd have fucking died if my old girl had turned up in that smoky cortina,ten years after it should have scrapped!!Have a good chat and explain it's unnacceptable to bite anyone,hit teachers etc,kids all need to respect rules/authority but again be able to stand up when they feel it's right to,it's the same in adult life.it'll be nothing major I'm sure and although some punishment is required,I think a really long chat,cuddled up in bed or sofa perhaps will reveal far more.