Jennie Shanker committed to teaching two classes in sculpture at a Philadelphia college for the spring 2012 semester. She turned down other teaching offers to keep that commitment.

One week before the semester began, the college abruptly canceled one of the classes because it was one student shy of its enrollment target.

"That was half my income," said Shanker, who earns $3,000 to $5,000 per three-credit course.

Such is the plight of an adjunct professor.

Adjuncts work without benefits or job security, often for little pay and with no stable career path, though providing a substantial portion of the higher education workforce.

One of the nation's largest teachers' unions is out to change that.

The American Federation of Teachers has quietly begun an effort to organize into one union the 15,000 or so adjunct professors who work at 43 public and private colleges within a 30-mile radius of Philadelphia. The goal is to form a bargaining unit that will negotiate contracts for the adjuncts and help them get health care and other benefits.

Shanker, daughter of the late Al Shanker, a legendary union leader who headed the AFT for 23 years, was one of the first to join the group - United Academics of Philadelphia.

"I honestly think if schools don't start treating adjuncts better, it's going to hurt these institutions," said Shanker, an adjunct for 16 years, mostly at Temple University's Tyler School of Art, University of the Arts, and Moore College of Art & Design.

The effort underway in Philadelphia is part of a national trend by unions to organize adjuncts in large cities, including Boston and Los Angeles, where the Service Employees International Union has taken the charge.

"Adjuncts are contingent workers who are exploited in lots of different ways," said Randi Weingarten, president of the AFT, which represents 200,000 employees in higher education nationally, 65,000 of them adjuncts. "This creates a way for them to have some power."

The AFT hopes to form bargaining units at some colleges by the 2014-15 academic year.

Adjuncts already belong to unions at Rutgers, Community College of Philadelphia, Bucks and Montgomery Community Colleges, and the 14 universities in the Pennsylvania State System of Higher Education.

AFT represents all but the state system school adjuncts, who are part of the Association of Pennsylvania State College and University Faculties.

At Rutgers, an AFT spokesman said, the unionized adjuncts won yearlong job contracts, higher pay, and the option to buy in to health care. Adjuncts at Philadelphia's community college earn seniority and the college contributes toward their health-care premiums based on that seniority, the spokesman said.Nationally, adjuncts represented by unions earn more money on average than those who aren't, according to a study by the Coalition on the Academic Workforce. Adjuncts who are represented earn median pay of $3,100 per course, compared with $2,475 for those who are not.

In Philadelphia, the union plans an aggressive push for members in the spring. If enough professors join, the union will petition for collective-bargaining rights to represent the group and seek to negotiate contracts, college by college. Thirty percent of eligible adjuncts must sign up to hold an election. To become a bargaining unit, more than 50 percent of the voters must approve.

At Temple, the adjunct faculty has tried to organize over the years, most recently in 2010. Temple employs more than 1,600 adjuncts, not far behind its full-time teaching force of 2,052.

"It was just a failure to engage enough people. It's hard work to track people down, find out who they are," said Art Hochner, president of Temple's faculty union. "The university doesn't give you a helping hand."

Hochner was heartened to hear of the new effort by adjuncts.

"The working conditions are poor and the pay is low," he said. "They don't get much say in anything. The students are being shortchanged, and the faculty are being shortchanged."

Sharon Boyle, Temple's associate vice president for human resources, said in a statement Temple "values and respects" its adjuncts as "a vital part of the university's mission to provide our students with a quality education. . . . We have taken steps in recent years to acknowledge the value of continuing employment of adjuncts by offering valuable benefits such as health care."

Hochner, however, contended that the health care is too costly to be worth it.

Ryan Eckes, an adjunct for eight years who taught four courses this semester at Temple and the city's community college, said adjuncts get no say in the direction of their academic department and no place to share ideas and help one another find jobs.

"No one has our backs," said Eckes, 34, of South Philadelphia, who teaches English composition. "The main thing is that you don't know where you'll be working next semester."

The title adjunct means "supplementary rather than an essential part."

"Even though we're half the workforce, we're not considered essential," said Eckes, who got his master's at Temple and has sought a full-time position.

Some adjuncts teach on the side while maintaining a career in law, business, or another area. But many also try to make it their primary source of income, often teaching at multiple colleges simultaneously.

Shanker has tried to get a full-time job and for six years was on one-year contracts. She's taught as many as seven classes a semester - "it was a lot of running around" - this semester, she's teaching only one.

"It's feast or famine," said Shanker, who has two master's degrees, one from the Yale School of Art and the other from the University of the Arts.

She does carpentry and art consulting on the side to make ends meet.

Looking back on her father's work, she said she understood firsthand the importance of a union.

"I wish he were here," Shanker, 49, of Fishtown, said of her father, who died in 1997. "These are unfair labor practices. I could be teaching and I could be on unemployment at the same time."

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