By David Greene | Originally Published in The New York Times, April 30, 2013

To the Editor:

What makes a great teacher? Not every college graduate is cut out to teach, regardless of his or her innate intelligence, G.P.A. or previous career success. Only those with specific talents and training become gifted teachers who, working with a talented mentor teacher and a variety of tools and learned techniques, can motivate students to want to learn.

As a former mentor to Teach for America corps members, I have seen their tears, anxieties, heartaches, successes and achievements. Unfortunately, the latter are far fewer. I have seen novices train novices to follow simple, formulaic scripts. They can do so much more if better prepared.

Corps members should intern for a year under the supervision of a talented mentor teacher, then teach for at least four years, not two. That may discourage some. Good. We want career teachers. A “temp” work force does not improve education or erase the achievement gap. Rather it helps to create havoc in schools desperately trying to gain stability, a key factor in any school’s success.

Teach for America has changed since its inception as a Peace Corps for American education. Then, I was in support of its efforts. Not now. Today’s Teach for America has morphed into more of a leadership institute.

It describes itself as a “growing movement of leaders, nearly 28,000 strong,

[that] works at every level of education, policy and other professions, to ensure that all children can receive an excellent education.”

Seasoned professionals know what works: being creative, independent, spontaneous, practical and rule-bending. Often it is the least orthodox teacher who most engages and excites students. Scripts and rules and models strictly followed cannot replace what the best teachers have: practical wisdom. In our anti-teacher world and scripted teaching climate perpetuated by corporate reformers, what room is there for the teachers we want for our kids?

David Greene
Hartsdale, N.Y., April 29, 2013

The writer is a staff member of WISE Services, which offers programs for high school seniors, and treasurer of Save Our Schools.

Editors’ Note: We invite readers to respond by Thursday for the Sunday Dialogue. We plan to publish responses and Mr. Greene’s rejoinder in the Sunday Review. E-mail: letters@nytimes.com