Every time I hear about a school where there are allegations or proof of cheating on standardized testing, I reflexively think about roaches, or, rather, the adage that if you see one or two of the pests running across the floor, there are probably an army of others having a party in the kitchen.

In city after city, we have recently heard about a stream of new cheating or suspected cheating revelations which, apparently, prompted Education Secretary Arne Duncan to send a letter late last week to the country’s state education secretaries on the importance of safeguarding the testing process, according to a copy published by the Baltimore Sun.

When D.C. school officials, for example, threw out the scores last month from 2010 standardized tests from three classrooms, who really thought that the problem was limited to those three?

After all, back in 2009, my colleague Bill Turque wrote about an investigation into possible cheating at 26 public and public charter schools where reading and math scores had shot up in 2008. The administration of then-chancellor Michelle Rhee, who had touted rising test scores as proof of the success of her reforms, never got to the bottom of the allegations then.

Then, last March, USA Today published its own investigation, saying that erasures had been flagged as outside the norm at 103 schools — more than half in the system — at least once since 2008. The D.C. Inspector General is conducting a probe.

Over in Baltimore public schools, Chief Executive Andrés Alonso disclosed last week that an 18-month investigation had uncovered widespread cheating on Maryland School Assessment tests (last year, a different elementary was caught for cheating in 2008) at two elementary schools. And, he told the Sun, two more schools are under investigation. Maybe that’s all. Maybe it isn’t.

Look at a map of the country and you can find cheating scandals in districts on the coasts and in the center, too: Florida, New York, Texas, California, Ohio, etc.

So Duncan urged state superintendents of education to step up and tighten security by:

* Reviewing and, if necessary, strengthening your efforts to protect assessment and accountability data, ensure the quality of those data, and enforce test security.  Among the steps that you can take are:

* Conducting a risk analysis of district- and school-level capacity to implement test security and data-quality procedures.

* Ensuring that assessment development contracts include support for activities related to monitoring test security, including forensic analyses.

* Conducting unannounced, on-site visits during test administration to review compliance with professional standards on test security.

* Seeking support to enact strict and meaningful sanctions against individuals who transgress the law or compromise professional standards of conduct.

Duncan’s letter does not discuss the cost of taking these measures or where cash-starved school districts are supposed to get the money from.

Cheating is nothing new, of course. And we often hear education officials say that the actual incidents of cheating represent a tiny percentage of all the tests taken. (Alonso in Baltimore said so; he’s either right or wrong.) But (as with roaches), who is willing to bet that there isn’t a lot more cheating than we know about? Besides, the difference with the test cheating of today as opposed to that of yesteryear is that now it is the adults who are the culprits in the limelight (which isn’t to say that kids aren’t cheating, too).

The adult participation is a result of the rise of the high-stakes standardized test as the main tool for evaluation — of students, schools, and now, teachers and principals. The testing emphasis started under No Child Left Behind and has continued under the Obama administration’s Race to the Top. And with more states passing laws to link teacher/principal evaluation to standardized test scores, educators’ careers will increasingly depend on an evaluation system that assessment experts say is unfair.

So we are sure to hear stories in district after district, year after year, about test booklets that were fooled with, and educators who cheated, and horrified system officials who tightened security to make sure it never happens again. Until it happens again.

Wouldn’t it be interesting to declare a national amnesty so that every teacher, principal and anybody else who cheated on a standardized test could come forward and explain how and why?

Then we could really see the extent of cheating and if, and how, our test-driven accountability system is compromised beyond its inherent unreliability.

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