On January 20, 2009, Sen. Barack Obama (D-IL) will be sworn in as the 44th president of the United States. Around the same time, millions of college students across the country will be beginning their spring semesters. And these classes will arrive with sizeable tuition bills. Obama has a plan for helping students tackle these costs -- a tax credit for students who perform community service. But the president-elect should take note. Tinkering with the tax code is a less than ideal way to promote college access and affordability.

The cornerstone of Obama's college plan is the American Opportunity Tax Credit. Worth $4,000 annually, it is available to all college students, regardless of income, so long as they complete 100 hours of public service during the academic year. The tax credit is fully refundable, meaning that if a student's tax liability is less than $4,000, they will have their tax bill paid off and then receive a rebate for any leftover credit amount.

On paper at least, the American Opportunity Tax Credit (AOTC) appears far better than existing higher education tax credits. This is especially true with respect to the Hope and Lifetime Learning tax credits, which were championed by Obama's Democratic predecessor Bill Clinton. The Hope credit is worth up to $1,650 (100 percent of the first $1,100 spent on higher education and 50 percent of the next $1,100) for the first two years of postsecondary enrollment. The Lifetime credit, meanwhile, is worth up to $2,000 (20 percent of the first $10,000 spent on higher education) and may be taken so long as students are enrolled.