Smith’s oldest son played a couple of years of youth football, but his two younger sons are not following him. Smith hears more about baseball, basketball and soccer these days. Football, he said, is more of “an acquired taste.”

“Once a society gets to know something is unsafe, we forget there was a time that we didn’t,” he said.

Changing Attitudes

The way Jim Harris saw it, someone had to stand up and say something, even if people in this town of 25,000 that is a half-hour’s drive from the Louisiana border were not receptive.

After years of reading about medical studies, reports about former N.F.L. players with long-term brain damage and lawsuits alleging that the National Football League hid the dangers of repeated head trauma, Harris concluded that football, the heartbeat of every town in Texas, was doing more harm than good.

A retired doctor with no shortage of opinions and a compulsion to share them, Harris rejects the argument that football is no more dangerous than, say, lacrosse or hockey if it is played the right way. He has taken his case to the local Boys & Girls Clubs, the school board and almost anyone else who will listen.

“The pot needs stirring,” Harris said. “Someone has to start to say we don’t need to play football. If it’s harmful to kids, then it shouldn’t be done.”

Image Bryan Partee, the executive director of the Boys & Girls Clubs of the Big Pines, who expanded flag football to include 8- to 12-year-olds. Credit... Brandon Thibodeaux for The New York Times

Harris’s campaign has, at times, been a lonely one. But more and more people here seem to share his concerns. Some older parents regret having let their children play the game, while young couples are weighing whether, or when, to let their children begin participating in tackle football at all.