One of the biggest issues in Prince George's County is the high number of teachers who are either not fully certified to teach or who are certified to teach one subject but are assigned to teach another. This is a problem that the new superintendent, Iris T. Metts, began to tackle practically the first day on the job, but I thought it would be interesting to review how this issue has emerged, not only in Prince George's but throughout the country.

To really understand this issue, it is necessary to know that for decades, teachers have been told that almost nothing they do has any effect on children's academic achievement. The basis for that was a study conducted in the late 1960s by a respected researcher, James Coleman, who studied available educational data and concluded that teachers and schools had a small effect on student achievement.

Coleman attributed almost all student achievement to things that students brought with them, with heaviest emphasis on the income, race and education of their parents. It is hard to overemphasize the baleful influence that report had on American education, but one of the worst effects was on teachers and principals, because being told you have no effect is dispiriting.

A corollary effect was to deemphasize the importance of teachers being fully trained and qualified to teach the subjects they were teaching. The thinking was that if they didn't have much of an effect, it didn't really matter. Meanwhile, most parents have been oblivious to this line of thinking. They know intuitively that it makes a difference how much their children's teachers know and how skilled they are.

This clash of thinking is the source of much friction between parents and school systems. The good news is that there is now some excellent research that counters the Coleman report and affirms the intuitive knowledge of good teachers and parents that schools, curriculum and teachers can make a huge difference in how much students achieve academically. One of the most important pieces of research in recent years documented a link between student achievement and how much teachers know about the subjects they teach.

To those outside the education world this seems so self-evident as to qualify for the title of " 'Well, duh,' research." And yet it directly opposes decades of common educational practice that has relied on the seeming truism, "A good teacher can teach anything." That self-justification has allowed many a high school principal to assign social studies teachers to teach sections of math, leaving teachers unhappy and students unable to understand quadratic equations.

The new research that links what teachers know to student achievement leads to a whole new line of action on the part of schools. Instead of simply giving up and having many schools try to be second-rate social service agencies (on the grounds that they were not going to be able to achieve much academically), you see a renewed interest in questions of teacher certification, teacher quality, teaching assignments and professional development of teachers, because those things are directly related to student success. It is because of this new research that we are all becoming uncomfortably aware of the high number of provisionally certified teachers in Prince George's County and elsewhere in the country.

Even those teachers who are qualified to teach one subject aren't necessarily qualified to teach another. Linking student achievement to teacher qualifications leads to more questions about what other factors are important to student success. There's been some excellent research in the last couple of decades on particular curricula and teaching methods, and it turns out that students who take a rigorous academic curriculum achieve at higher levels than if they don't.

"Well, duh," you might say again, but for years, U.S. schools operated on the assumption that some students would achieve and needed a rigorous curriculum, and others would not achieve and needed a less rigorous curriculum. That led to enormities such as the one documented by the U.S. Department of Education that, nationally, the longer students are in high school vocational programs, the lower their reading levels are. (That is, seniors finishing up four years of vocational education have lower reading levels than freshmen just starting vocational education).

In fact, the U.S. Department of Education just published a major study that found that the best predictor of whether students would receive a bachelor's degree was whether they took a rigorous high school curriculum.

If they didn't take that curriculum (and one of the keys was math past Algebra II)--even if they got good grades, had a high class standing and good SAT or ACT scores--they were less likely to finish college. Yet more research has documented a link between student achievement and the time students spend learning, known as "time on task."

Again, this seems so obvious as to not need stating, but it runs counter to decades of educational practice, in which academic time has been intruded upon by lots of faddish nonsense that educators and politicians thought were good ideas but had no relationship to what children need to learn. So, slowly--too slowly--the field of education has been creating the building blocks of what will ultimately put education on a real professional footing, with common standards of achievement and ways to link that achievement with what teachers and schools do. But we're not there yet.

Right now, education is still called an "immature profession," somewhat akin to medicine 100 years ago, when anyone could call himself a doctor, grind up chicken livers and call the result a cure for liver cancer.

Medicine has come a long way since then. It has a scientific approach to studying disease and a protocol for testing possible cures. Medicine now has a standard training expected of all its professionals, including not only doctors but also nurses, physician assistants, and so on.

We are moving toward building improved standards in education, and one of the first pieces to be put in place is the certainty that teachers need to be well grounded in the subjects they teach and in the best ways to teach children.

That's the long explanation of why there is such an interest in teacher credentials. And it's about time.

Looking for Crossing Guards

Dear Homeroom:

How does the school system assign crossing guards near elementary schools in Prince George's County? At the intersection of Prince Place and Harry S Truman Drive (a four-lane divided highway), there have been two guards for the past several years--one each for the northbound and southbound lanes. This school year, there has been only one. Is this change due strictly to budgetary reasons? Have any studies been done to show that a single guard is adequate and that this change is justified?

Steve Brown

Upper Marlboro

Actually, crossing guards are not assigned by the school system at all. They are assigned by the Prince George's police department.

And Charlotte Moreland, the police department's crossing guard supervisor, says the reason is a "shortage of manpower," not any attempt to cut costs. She has been trying very hard to find more crossing guards but is still 10 short of the 137 she is allocated to cover 500 intersections.

"As soon as we can, I'm going to get someone there," she said about the intersection you mention. However, she said, she has assigned an experienced, confident crossing guard there.

Although the situation is not ideal, Moreland said, it is still safe.

As long as we were talking, though, Moreland asked me to make a recruiting pitch for crossing guards. Many stay-at-home parents and retirees find it to be a great job.

"They like being out in the elements, and they love the kids," Moreland said. "It gets in your blood."

Plus, you get full medical and pension benefits, paid holidays and $35 a day to work 7:30 to 9 a.m. and 2 to 4 p.m. But be prepared for a full background check. Once you're done, Moreland said, the file on you will be "an inch thick."

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