Need advice about 3 yr olds!!!!

[mattsmom]

Please help!!! I'm at my wits end with these 3 yr olds

I have 4 of them at the moment and I don't know what it is about this age, but they are driving me nuts! It seems they were utter angels at 2 yrs and then BAM!!! they turn on me!
The problems are: constant tattling, taking toys from one another, not listening and the whining....oh the whining!!!
I've tried timeouts for taking toys etc, separating them, encouraging cooperation, you name it and I've tried it....I don't know what to do!

Any advice would be appreciated