Like losing favorite uncles, millions of us have grieved in the past year at the deaths of Bob Keeshan, the creator of “Captain Kangaroo” on CBS, and Fred Rogers, who developed “Mister Rogers’ Neighborhood” on public television.

Perhaps this sense of loss helps explain why “The World According to Mister Rogers,” a book of writings, has been on the The New York Times best-seller list for months, and two more compilations are planned. “There’s something deeply satisfying,” a columnist wrote in The Detroit Free Press, “about seeing Fred Rogers emerge, a year after his death, as a spiritual guide.”

Satisfying, but not so surprising. When these men began their programs in the mid 1950s and 1960s respectively, “Captain Kangaroo” and “Mister Rogers” were unusual for their gentleness and slow pacing — and for taking children seriously, as an audience to be enlightened as well as entertained. Both hosts would break the “fourth wall” of television — the screen — and talk directly to children.

The first time I professionally watched children watching television, two preschool sisters were viewing “Mister Rogers.” At times they watched intently, at times they played with toys or each other, but throughout, they kept up a running dialogue with Mr. Rogers. He and the Captain knew that young children are intellectually and emotionally involved with programs that respect their level of development.

The effects are traceable for years, as we found when my colleagues and I interviewed and reviewed the transcripts of high school students we had studied as preschoolers in the early 1980s. The more these teens had watched programs like “Captain Kangaroo,” “Mister Rogers” and “Sesame Street” as preschoolers — the Captain aired on CBS from 1955-1984 and on PBS until 1990, Mister Rogers ran on PBS from 1968-2001, and “Sesame Street” started on PBS in 1969 — the better were their high school grades in English, math and science. They also read more books for pleasure, and were less likely to endorse violent solutions to hypothetical social problems.

Viewing “Sesame Street” best predicted higher high school grades and book reading; viewing “Mister Rogers” predicted creative activity in areas such as art, music and creative writing. This was true, regardless of parents’ education, family size, preschool intelligence and the like.

Unfortunately, programs designed to benefit children were only a small part of children’s overall TV viewing diet. Beginning in the early 1960s commercial children’s programs became increasingly animated, fast-paced and violent, designed as vehicles to deliver children to advertisers. Researchers discovered that children incorporated the violent imagery and themes into their play. TV violence was associated with undesirable outcomes, including youth violence and poorer school achievement.

Today, children’s television has gotten better, especially for preschoolers, and I think we can largely thank the gentle pioneers for it.

The Children’s Television Act, passed after lobbying by Keeshan and others and implemented in 1996, mandates that broadcasters provide at least three hours a week of programming designed to be beneficial to children.

Of course, in its totality, children’s television remains far from wonderful. While there are excellent programs for older children, they are relatively few. As we move to new technologies and to less regulation, it is far from clear that programming will continue to improve.

But I am optimistic. Keeshan, Rogers and the wonderful people who created “Sesame Street” showed us the possibility, and there are many more parents-to-be coming along who grew up under their spell.

Daniel R. Anderson is professor of psychology at the University of Massachusetts.