Editor’s note: William J. Bennett, a CNN contributor, is the author of the newly published “The Book of Man: Readings on the Path to Manhood.” Bennett, the Washington fellow of the Claremont Institute, was U.S. secretary of education from 1985 to 1988 and was director of the Office of National Drug Control Policy under President George H.W. Bush.

(CNN) — A good teacher not only improves a child’s test scores in the classroom, but also enhances his or her chances to attend college, earn more money and avoid teen pregnancy, according to a new seminal study.

The study, conducted by economists Raj Chetty and John N. Friedman of Harvard and Jonah E. Rockoff of Columbia, tracked 2.5 million students over 20 years from a large urban school district from fouth grade to adulthood, making it one of the largest and most consequential educational studies in recent years.

Their findings focus on the long-term impact of teachers based on their “value-added” ratings. This refers to the average test-score improvement for a teacher’s students, adjusted for differences across schools and classrooms such as prior test scores. Evaluating teachers based on student performance has been the subject of much debate among teachers, unions and policymakers.

William Bennett

Teachers and teachers’ unions have been largely critical of the value-added approach, arguing that test scores are not good indicators of teacher quality. However, many reformers, like Stanford’s Eric Hanushek, argue that value-added ratings are some of the most accurate indicators for evaluating teachers and improving student performance.

This study puts the value-added approach to the test in a new way, measuring the short-term impact in the classroom as well as long-term impact, like a student’s collegiate, career and family success. The authors found that “when a high VA teacher joins a school, test scores rise immediately in the grade taught by that teacher; when a high VA teacher leaves, test scores fall.”

Most importantly, the study discovered that “students assigned to higher VA teachers are more successful in many dimensions. They are more likely to attend college, earn higher salaries, live in better neighborhoods and save more for retirement. They are also less likely to have children as teenagers.”

The effect of a good teacher on a child’s life is monumental. In financial terms, the study notes that replacing a teacher whose true value-added is in the bottom 5% with a teacher of average quality would generate lifetime earnings gains worth more than $250,000 for the average classroom.

On the other hand, “If you leave a low value-added teacher in your school for 10 years, rather than replacing him with an average teacher, you are hypothetically talking about $2.5 million in lost income,” said Friedman.

The authors, two of whom were skeptical at first of the merits of value-added metrics, conclude the study by recommending that schools adapt value-added measures and fire the lowest-performing teachers.

Given the enormous contribution of good teachers to the lives of students, one would think the organizations that represent teachers would hail this study and disseminate its findings. This is not so.

Predictably, the teachers’ unions have been silent. Acknowledging the realities of this study would require the unions to make distinctions between good and bad teachers and hold them accountable for their performance, something they seem incapable of practicing, much less institutionalizing.

It is ironic that a report that praises great teachers seems to be ignored by teacher organizations.

This study shows that, second only to parents, teachers are the most important part of a child’s education. Great teachers make a great difference; poor teachers hurt a child’s life chances. Isn’t that all we need to know to embark upon a serious effort to reward good teachers and encourage poor teachers out of the profession?

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Finally, at about the hour and a half mark, I saw Travis. I almost burst into tears upon seeing him, but kept my composure. “Thank God!” I gasped, “I thought you left without me!” Soon after, M. Denizot appeared, and we introduced ourselves. “Je suis très heureuse pour vous voir, ” I said, as I had to Travis, “J’ai pensé que vous êtes sortis sans moi!” But, as I soon learned, I could not breath easy yet. Emma was missing! Her plane had in fact landed, Travis and M. Denizot told me, and she had been on it, as they had confirmed at the information desk, but she was no where to be found! I asked if they had tried to call her, and, discovering that they had not, I whipped out my phone. “Sorry dad,” I thought as I dialed her number on my American cell phone for the 4th time that day (I had tried to call her several times when I was lost myself). She didn’t answer. I tried again. She didn’t answer. Finally, I got a hold of her, and we learned that, after arriving and looking for Travis and M. Denizot at her terminal (the same one at which Travis arrived) for the better part of an hour, she had attempted to go to my terminal, thinking that perhaps she had misunderstood and was meant to find us there. However, the attendant at the information desk gave her the wrong information, and she was sent to Terminal 2D. I was at 2A. To make matters worse, when we called her, M. Denizot misunderstood her, and we ended up at 2B. Finally, after about another half hour, we found Emma, and we were able to get in the car and drive to Amiens, which was about an hour and a half away.For most of the drive, Emma and Travis slept, and I spoke with M. Denizot (in French!). I was thrilled that I was able to understand and converse with him, and also very thankful that my trip to England prior to my arrival had adjusted me to the time change, as I knew my brain would not be working as well if I, too, had just arrived in Europe.

When we arrived in Amiens, we went to L’IUFM (the education college) to eat lunch and meet a few of the professors. Perhaps most importantly, we met Anne Petit, who will replace M. Denizot when he retires. We also learned that she, and not M. Deinzot, would be the one with whom we will be working for the rest of our trip. Lunch was a bit overwhelming, as they all spoke very quickly in French, but after telling them that, they slowed down, and, to our relief (especially for pour jet-lagged Emma and Travis), Anne spoke in English for the rest of the day. She actually has a British accent when she speaks English because she taught there for a few years. She took us to check into our dorm rooms, and then showed us around the town a little bit and took us to the grocery store to buy essentials for the weekend, promising that we would have more time to shop at a larger grocery store later. We also each received “Une Carte Monéo” (Monéo Card), with which we pay for our meals at the University restaurants (for only 3 euro a meal!) Anne was enormously nice and helpful, and we were able to get ourselves settled in. The room is very small, but the view from my window makes up for it:

After we had moved in and Anne left us, the three of us went to the cafeteria for dinner, and then explored Amiens a bit. Emma and I actually ended up getting a little bit lost, but we are always able to find our way back to our dorm room by looking for the steeple of the beautiful cathedral we can see from our bedroom windows. Then, we returned chez nous (home), where we unpacked and then went to sleep.

Today, Jenny, one of the girls who came to Oklahoma from Amiens in March, and who was born and raised in Amiens, took us around the city, showed us how to take the train and the bus (the train for trips to Paris and other cities, the bus for getting around town), and gave us a brief introduction to all things Picard (“Picard” is the adjective describing things from the region of Picardie, where Amiens is located… picard:picardie :: french:france). We got to see the inside of the cathedral (it is the tallest in France, we are told), and I took many pictures, which I will post on facebook. We will go back there for a formal audio tour and to climb the tower next week as part of one of our courses. We also tried un macarron (a macaroon), which was invented in Amiens, and therefore is known as its specialty. It was delicious!  After our tour of the city, we said “Au Revoir” to Jenny, and we returned home with very sore feet! There is hope for me losing weight in France yet!

Overall, the trip has been wonderful thus far. The city is gorgeous, we know how to eat and a little bit about where to go, and have met some wonderful people. The beginning was rocky, but if that is the worse thing that happens, we are doing very well for ourselves. Travis and Emma are napping now, so I have time to update, and I will begin working on some of my schoolwork for the independent study I am doing while here. Later, we will all meet up to go into the city center (which Jenny showed us earlier) to eat dinner in a pub, cafe, or resto (“un restaurant” is often shorted to “un resto”) there.

A demain (until tomorrow),

Felicity