All you need to break the code

Charitable receipts. The IRS will no longer take your word for the $20 you put in the collection plate each week, said Mark Luscombe, federal tax analyst at CCH Inc., an Illinois-based publisher of tax information. You need to either write a check or get a receipt for every donation. This documentation does not need to be sent with your return, but you should keep it just in case you're audited.

AMT credit. If you paid the alternative minimum tax in a prior year because of a phantom gain, you might qualify for a refundable credit in 2007, Luscombe said. The credit phases out for singles earning more than $156,400 and married couples earning more than $234,600.

This break was designed to help former dot-com workers who received incentive stock options during the boom, only to have the value of these options evaporate later.

Many of these people owed hundreds of thousands of dollars in tax on phantom gains because of a glitch in the AMT law. They had complained for years that they were being made destitute by taxes owed on gains that had never materialized. This credit helps some in this group, those who paid AMT taxes prior to 2004, reclaim a portion of those taxes.

Song sales. If you wrote a song -- or inherited one -- and sold the rights for a profit, you get to take preferential capital gains treatment on the sale. That can save some songwriters 20 percentage points in tax.

Child exemptions. The clarification of rules stipulating who can claim a child as a dependent allows some unmarried partners and grandparents to take tax write-offs for children they support who might live with a parent.

Kids and taxes. Children under the age of 18 may have to pay tax on unearned income at their parents' marginal rate. (The old law threatened kids with being subject to their parents' rates only until the age of 14.) Full-time students can be subject to kiddie tax rules until they're 24.

Here today, gone tomorrow

Two popular breaks expired in 2007, giving taxpayers one last chance to claim them.

Tuition and fees. Your 2007 tax return is your last opportunity to claim the tuition and fees deduction, a lucrative break for taxpayers paying college bills for themselves or a dependent.

Like many other tax breaks, this is income-tested. Singles earning less than $65,000 annually and married couples with less than $130,000 in adjusted gross income can claim a write-off of up to $4,000 for college costs paid last year.