Though the recession has forced schools to curb hiring and layoff some teachers - in addition to giving veterans second thoughts about leaving their jobs - some observers warn that it's just a temporary hiatus.
"The shortage is not over," says B.J. Bryant, executive director of the American Association for Employment in Education, which publishes an annual survey of teacher supply and demand each fall.
Yet recent research suggests that fears of empty classrooms may be exaggerated. The nation's colleges produce more than enough teachers - although graduates don't necessarily migrate to the regions and fields that need them most.
Shortages are confined largely to schools in the Sunbelt as well as urban and rural communities. Similarly, slots in specialties such as science, math, and special education remain hard to fill.
That problem will only grow worse under the No Child Left Behind Act that stiffens certification requirements for specialties. For example, districts will no longer be able to place a teacher with a general science preparation in a position requiring certification in biology or physics.
And in these hard-to-fill specialty areas, attrition proves particularly troublesome: Special education or science teachers are twice as likely to quit teaching as social studies teachers.
The price associated with such high turnover is tremendous. In Texas, for instance, the loss of 40 percent of new teachers during their first three years is estimated to cost the state between $329 million and $2.1 billion in termination, recruiting, and training expenses.
Some of the reasons teachers leave the profession are fairly obvious, says Richard Ingersoll, an education and sociology professor at the University of Pennsylvania. Salaries are low. Verbal abuse is often part of the job.