DETROIT (AP) _ Two 8-year-old boys and a 7-year-old girl held hostage by a gunman at an elementary school remained calm and even helped their captor by looking out the window for him during a four-hour siege, police said.

The unidentified man slipped into the second-grade classroom at William C. Loving Elementary School on Tuesday, then told police he wanted a car, some cash and a ''new start in life.''

He fired shots into the classroom ceiling, but released the hostages unharmed four hours later.

Police Cmdr. Jerome Miller said the children remained calm and even seemed to have fun. ''They were kind of playing,'' he said. ''They were helping him, looking out the window for him.''

''He's a nice man,'' hostage Landrus Thomas said after his release. ''He asked the police if we could have some pop. He didn't try to harm us or nothing.''

A suspect described as a jobless 19-year-old from adjacent Hamtramck was being held today pending formal charges, Sgt. Daniel Carr said.

In addition to Landrus, 8, Miller identified the hostages as Jesse Payton, 8, and Tennille Wilson, 7.

The gunman mingled with parents to enter through the only one of 14 doors that was unlocked at about 11 a.m., Detroit Public Schools Superintendent Arthur Jefferson said.

He went to Room 174 and sat on a stool near the teacher's desk, the superintendent said.''The teacher asked him 'How may I help you? Do you have a child in this room?''' Jefferson said.

''He said 'I need help,''' Jefferson said, adding the man then reached into one of two garbage bags and pulled out a .22-caliber rifle.

The gunman said he ''wanted a new start in life'' and demanded a car and $8,000, Miller said.

''He wasn't incoherent,'' said Deputy Police Chief James Bannon, who described the man as ''very intelligent, seemingly bright, well-spoken and very polite.''

During the siege, police granted a request for food, delivering soft drinks, chips, peanut butter sandwiches, cigarettes and a radio the gunman said he wanted.

Police had been negotiating with the man when he came out of the room and threw down the gun, Miller said.