Somewhere inside a giant crater on the moon lies a small silver pin in the shape of a shooting star.

It's been there since Nov. 19, 1969, when then-Navy Capt. Alan Bean tossed it in.

"I had worn it for years," Bean told students yesterday at Arlington Traditional School. The pin had been awarded to him in the mid-1960s after his first year of astronaut training. "Now sometimes at night, I look at the moon . . . and I think about that shiny little pin."

As part of the Apollo 12 crew, Bean, now 73, was the fourth man to walk on the moon's surface and one of only 12 ever to do so. He says he was also the first to eat spaghetti there.

Bean, who lives in Texas, generally is paid to speak at corporate events, but the Arlington school had an inside connection: His grandson James Mellin, 9, is a fourth-grader there, and James was grinning hugely as he walked his grandfather into the auditorium to a burst of student applause.

Bean told the students how it felt to be nearly weightless and showed pictures of himself as a boy and as an astronaut in training, including one of him in a moon gravity harness that, he complained, gave him a "spacesuit wedgie."

Bean said the trip made him realize how much he loved his own green-and-blue planet.

"With all our telescopes and all our spaceships, we've never seen a place as beautiful as this one right here," he said, adding that after his trip he never complained about the weather again. "If it snows, I'll think that's beautiful. If it rains, I'll be happy. If sandstorms come along, I'll like that, too."

Bean has had a second career as an artist, painting scenes of space exploration with paint that he has mixed with moon dust.

As Bean's wife, daughter, son-in-law and another grandson looked on, Principal Holly Hawthorne presented Bean with a brick similar to one that will be engraved with his name and built into the school's courtyard.

He then met with individual classes in the library to show students tiny moon rocks and answer questions.

Hands shot up.

"Do you think we'll live on other planets someday?" (He does and thinks the Olympics may be held on the moon one day.)

"How did you feel like when you were flying back?" (Excited to see his wife and children, whose picture he had carried with him.)

"Those gloves, are they really stiff so you can't move your fingers?" (The custom-made space suits fit perfectly and allow astronauts to move around pretty well.)

Afterward, fourth-graders speculated on how it would feel to visit the moon.

"Rocky and dusty," said Christine Nguyen, 9.

"Dark, and full of possibilities," said Ethan Grant, 10.

Asked whether they would like to go, Christine said, "Well, it seems a little dangerous." But Ethan said he would make the trip "to learn more about space, to see the amazing possibilities and things people haven't discovered yet."

Some visiting parents were even more excited than their kids. Edwin Yong, who named his 7-year-old son, Apollo, after the space missions, took off from work to be there. David Crockett whipped out a comb to smooth his 10-year-old son Edward's hair for a class picture with Bean.

As the students filed out of the library, Bean reached into his pocket for some "moon dust" and announced that he was sprinkling a little on each child's head.

"He put moon dust in my hair," squealed a first-grade girl.

A boy shook hands with Bean and then squinted down at his own hand, searching for dust.

Bean told them that one day they might bring their own dust home. "I would say that the young people that are going to be the first on Mars are just about your age," he said. "You're the right age to have some of these adventures."

And if they ever make it to the moon, he has a favor to ask. "I've got a gold pin now, but the silver one's sitting up there," he said. "I think it's going to be there until some of these kids go up there where I landed and get this pin and bring it to me."

Former astronaut Alan Bean, 73, sprinkles "moon dust" on student George Jobson Oliver, 8, during a visit to Arlington Traditional School. Bean is one of 12 astronauts who have walked on the moon.