In 2004, the University of Phoenix paid a $9.8 million fine, the largest ever imposed by the Department of Education, for allegedly pressuring recruiters to accept unqualified students. The Apollo Group admitted no wrongdoing.

For some critics, such tactics challenge the basis of for-profit education. But the business model isn’t new - and it's been very successful in the past.

Until the early 20th century, many lawyers, doctors and accountants learned basic skills at for-profit schools. But quality was uneven. Muckraking newspapers carried screaming headlines and stories about poorly trained doctors. By 1920, the number of medical schools had been cut about in half.

A variation on studying with a professional in your chosen field survives in the Chartered Financial Analyst, or CFA. The not-for-profit CFA Institute has 70,000 members, all of whom hold the professional designation.

The decline of for-profit professional study before World War I led to the creation of research universities that depend on Federal research grants, a variation of the University of Phoenix’s steady diet of federally backed student loans.

World War II and the GI Bill changed everything. Before the war, about two-thirds of the nation’s adults hadn’t completed high school. After the war, the percentage of people completing high school grew to 80%. Moreover, 21% had attended college and 15.5% earned a bachelor’s degree.

Critics decry what some call credentialing mania. Some fields -- journalism, for example -- now require college degrees for jobs that were once filled with “ink-stained wretches” who learned the trade on the job.

But the desire for a college degree isn’t just snobbery. The US Census Bureau reports that workers with a bachelor’s degree earn an average of $51,206 a year; those with only a high school diploma average $27,915. Workers with an advanced degree average $74,602, while those who don’t complete high school average $18,734 a year.

The earnings disparity creates great demand for a college degree. It also allows selective, big-name schools to raise tuition faster than the rate of inflation, while for-profit schools must remain affordable to be competitive.

If you or your kid is fretting about the SAT or the admission test required by a graduate or professional school, don’t overlook for-profit cramming. Kaplan, a leader in test preparation, is a subsidiary of the Washington Post (WPO).

If that doesn’t work, the University of Phoenix will be happy to take your money.

For more on grades for pay, check out Hoofy and Boo's always astute report.