President Obama told the students the rising cost of college is slowing efforts to strengthen America’s economic future. “Since most of you were born, tuition and fees have more than doubled. That forces students like you to take out more loans and rack up more debt,” he said.

The president said Friday that his administration has helped to make higher education more affordable by giving more federal money to students who need it. But he said rising tuition costs at the nation’s universities makes the program more difficult for even the government to afford.

“We cannot just keep on subsidizing skyrocketing tuition," Obama stated. "If tuition is going up faster than inflation, faster than even health care is going up, no matter how much we subsidize it, sooner or later, we are going to run out of money.”

Part of Obama’s plan is to withdraw or reduce federal funding from universities that fail to control their tuition costs. “We are putting colleges on notice: You cannot assume that you will just jack up tuition every single year. If you cannot stop tuition from going up, then the funding you get from taxpayers each year will go down," he said. "We should push colleges to do better.”

The president also said he wants to begin a competition to encourage states to better use money for higher education. The winning state would receive a $1 billion prize.

“We are telling the states: If you can find new ways to bring down the costs of college and make it easier for more students to graduate, we will help you do it,” Obama said.

He suggested another competition to encourage innovations to increase productivity on college campuses.

Friday’s speech concluded the president’s three-day, five-state tour in which he promoted the initiatives he discussed in Tuesday’s State of the Union address.

Much of Obama’s plan faces a difficult future in Congress, which must approve almost all of it.

Some Republicans have warned that moving federal aid away from colleges will hurt students, and that the president’s education plan will reduce the autonomy of the higher education system.

The proposals the president made in Michigan were an appeal to young voters and working families, two groups that usually support Obama, in one of the states that could decide the November election.

New poll numbers are encouraging for the president. An NBC News-Wall Street Journal survey shows that 48 percent of Americans think Obama is doing a good job, compared with 46 percent who disapprove. It is the first poll in six months that shows more people approving than disapproving.

The survey says 37 percent expect the economy to improve in the next year, compared with 17 percent who think it will get worse - a jump of seven percentage points from last month and a reversal from October.