STAFFORD TOWNSHIP, N.J. n In his Day-Glo orange New York Mets T-shirt and cap, 11-year-old David Jensen Jr. lives for baseball. He plays shortstop and pitches for his team, enjoys standing in the batter’s box and taking his swings against an opposing pitcher, and loves nothing better than the crack of the bat and the sweet trajectory of a long blast to the outfield. On a gorgeous fall afternoon this week, while other kids were playing with their Play Stations or watching DVDs, David was fielding ground balls hit by his dad, over and over again. ``I’ve been playing since I was 3, he said. ``It’s fun.’’ But not everyone looks at youth sports the same way. Jensen was playing across the street from where a Pop Warner football team had three of its coaches suspended last week for the remainder of the season for unsportsmanlike conduct including allegations of on-field profanity, the attempted assault of an opposing coach, and a threat of violence against a league official. The coaches deny any misconduct, and their team of 11- to 13-year-olds, after a league hearing, was permitted to finish its season with different coaches. Bad behavior at all levels of youth sports - by players, parents and coaches - is a nationwide problem, one that a growing number of leagues and state and local governments are struggling to deal with. Fred Engh, president of the National Alliance For Youth Sports, formed his group in Florida 21 years ago to tackle bad behavior at youth sporting events after watching a father berate his 9-year-old son, who was pitching in obvious pain, grabbing his elbow and crying after each pitch. His father says to him, `Son, this is a man’s game. Get in there and pitch,’’’ Engh said. Each year, hundreds of instances of bad behavior at youth sports games - sometimes involving physical violence - make the news. For each that is reported, many more go unpublicized, said Engh, who wrote the book ``Why Johnny Hates Sports.’’ The most horrific occurred in 2000 at a Reading, Mass., youth hockey game in which one hockey father, arguing with another dad over rough play on the ice, beat him to death at the rink. Thomas Junta was convicted of involuntary manslaughter and sentenced to six to 10 years in prison. New Jersey has had its share of youth sports violence. In February 2003, a youth hockey coach was suspended after being charged with aggravated assault at a game in South Brunswick. He was one of the first to be charged under New Jersey’s recently toughened law against violence at youth sports events. The law upgraded such crimes from simple assault to aggravated assault with a jail term of five years as opposed to 18 months. In October 2003, a pre-game brawl between two coaches of the same youth football team in Franklin Township, Gloucester County, left one hospitalized and the other charged under the sports violence law. They were arguing over the amount of playing time one of their sons was getting. That same month, a youth baseball manager was indicted for punching an umpire during an all-star game in Hazlet. Why, when the vast majority of parents and coaches behave themselves, do some run amok at youth sports games? Engh suspects it’s because of a lack of training, immaturity on the parts of children and adults, and a desire among some parents to live vicariously through their children, to see Johnny hit the home run or score the touchdown that they couldn’t when they were kids. ``In the suburbs of New Jersey, if there’s a fast-growing section of town with 25,000 residents, they’ll build an elementary school,’’ Engh said. ``Suppose the board of education said to the parents, `We’ll let you run the school. You go recruit volunteer moms and dads to be the teachers and the principals.’ You’d say these people are nuts. But that’s just what we do with sports facilities. We never train people or educate them about what these things are supposed to be about, which is educating and entertaining children and letting them have fun.’’ Bob Burlew, president of the Jersey Shore Pop Warner Football League, said the organization suspended the coaches of the Southern Pop Warner Pee Wee Rams because they were out of control at several games this season. ``We have very little tolerance for coaches, fans or players who get out of control with the children,’’ he said. ``This situation got a little crazier than we could handle. We needed to address this.’’ William Shimko, one of the suspended coaches, could not be reached for comment. But he told the Asbury Park Press of Neptune he had never misbehaved on or off the field. David Jensen Sr., who was hitting grounders to his son at the Stafford field recently, coached baseball with Shimko, and said the suspended coach is beloved by his players and their families. ``He’s taken kids that don’t have fathers, and takes them out to baseball and football games, Jensen said. ``He’s a great coach.’’ Some leagues and municipalities are dealing with the issue of behavior. In South Plainfield and Nutley, parents who sign their kids up for youth sports must sign a code of conduct agreeing to behave themselves at the events, or risk being banned from attending them. Many leagues are now requiring volunteer coaches to undergo training or certification by amateur athletic associations before being permitted to take the helm of a team. And coaches are being more upfront with parents at the start of the season about what’s allowed in the stands and what isn’t.