The field trip, once woven into the American school experience, is in decline. More than half of schools eliminated at least some planned field trips in 2010-2011, according to the American Association of School Administrators. The practice might diminish even further if we don’t do something about it.

Like many adults, I have fond memories of visiting museums and factories when I was in school. I liked skipping class, of course, but some of those exhibits and industrial processes opened new perspectives on adult life. An unusual new study by the University of Arkansas reveals that even today children learn much from field trips that they can’t get from teacher lectures or textbook pages.

The Arkansas researchers, Jay P. Greene, Brian Kisida and Daniel H. Bowden, set up a randomized experiment involving more than 10,000 students. Some visited the new Crystal Bridges Museum of American Art in Bentonville, Ark., and some did not. All were then surveyed. Those who went on the field trip showed higher levels of critical thinking, historical empathy, tolerance and interest in art museums than similar students who didn’t. Even more impressive to me was the fact that those who went on the trip remembered important details weeks later.

“For example,” the researchers said in the “Education Next” quarterly, “88 percent of the students who saw the Eastman Johnson painting ‘At the Camp — Spinning Yarns and Whittling’ knew when surveyed weeks later that the painting depicted abolitionists making maple syrup to undermine the sugar industry, which relied on slave labor. Similarly, 82 percent of those who saw Norman Rockwell’s ‘Rosie the Riveter’ could recall that the painting emphasizes the importance of women entering the workforce during World War II.”

Critical thinking was assessed by showing third- through 12th-graders, both those who went and those who didn’t, a painting they had not seen, Bo Bartlett’s “The Box.” They were asked what they thought was going on in that work and to explain their conclusion. Their answers were scored on the number of times they showed engagement in observing, interpreting, evaluating, associating, problem finding, comparing and flexible thinking. Those who went on the trip beat those who didn’t by 9 percent of a standard deviation. They also did better on several other assessments.

The critical-thinking gap between field trip students from rural and high-poverty schools and similar students who didn’t go on the trip was significantly larger than the gap between affluent students who went and affluent students who didn’t go. The disadvantaged kids got more out of the experience because they got relatively less enrichment at home.

That reminded me of Rafe Esquith, my field trips guru. Esquith teaches a Los Angeles fifth grade full of low-income Hispanic and Asian children. Long ago he developed a system of taking students to plays, museums, concerts, ball games and other events after careful preparation for the experience. One of his four books is about how this worked at one Dodgers game. Actor Ian McKellen became an Esquith friend and booster after he noticed at a Los Angeles Shakespeare performance that a group of fifth-graders in the audience was mouthing every word he said. They already knew the play.

In the KIPP charter school network, created by Esquith disciples, each year ends with a week-long trip, the culmination of hours of lessons. In most schools such experiences are rare. They get less encouragement because school leaders think trips take time away from preparing for state exams. But KIPP students do very well on those exams. We need more such experiences, not fewer.