A.I.
I'm a CPA here in Plano.
In response to your specific questions. 1) Your status at the end of the year determines your status for the entire year. So if you're divorced by 12/31/2012 you will file as either single or head of household (if the kids are in your custody). 2) Childcare credits can only be taken by the parent who has custody AND pays the expenses.
That said I would encourage you to hire a professional tax preparer at least the first year and if possible even consult with one regarding the specifics of you custody arrangement before it is finalized. Tax effects of a divorce can be fairly complicated and it can be more costly to do it wrong and pay penalties to the IRS or miss tax benefits you are eligible for.
A. R. I., CPA
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