U.S. President Barack Obama speaks in Detroit on Wednesday. On Friday, Obama is expected to outline details of his plan to make the first two years of community college free for students. Reuters

President Barack Obama's plan to give two free years of community college to U.S. students was criticized by conservatives Friday for its lack of details, potential high costs and minimum grade-point-average requirement. Obama was scheduled to detail Friday the plan unveiled Thursday night, but domestic policy adviser Cecilia Muñoz told reporters he had already accomplished his main goal: "to start a conversation" about increasing access to college.

House Speaker John Boehner was not impressed. "With no details or information on the cost, this seems more like a talking point than a plan," his spokesman Cory Fritz said in a statement. Some news outlets estimated the effort would cost roughly $15 billion a year.

Obama's plan would give two free years of community college to "everybody who is willing to work for it," Reuters reported. Students would have to be enrolled at least half-time and actively work toward completing their programs. They also have to maintain a 2.5 GPA -- a C+ average -- which critics of the plan said was too low.

The proposal could save up to 9 million students $3,800 in tuition a year, and the federal government would foot 75 percent of the bill. States would pay the other 25 percent, ABC News reported. That's what some critics were concerned about Friday morning.

The proposal is based on the Tennessee Promise, which gives Tennessee high school seniors two free years at any state community college or technical school. Rep. Diane Black, R-Tenn., supported the Tennessee Promise but expressed frustration about the president's potentially pricey plan. "While the White House says that three-quarters of the program would be paid for with federal funding, I have yet to hear what offsets, if any, would be proposed to ensure Americans are not saddled with greater debt and deficits as a result," she said in a statement. "Will the president offer proposals to make his plan budget-neutral, or will he attempt to charge it to the credit card? Ultimately, any efforts to reboot Tennessee Promise as a one-size-fits-all nationwide approach will be met with heavy skepticism from Congress."

The debate also unfolded on social media. While many Twitter users posted messages in support of the plan, some tweeted that it was unrealistic, expensive and enabled low-achieving students.

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