White House West : Presidential library: Fourth-graders are shown a scale model by a knowledgeable guide--Nancy Reagan.

Former First Lady Nancy Reagan led a group of fourth-graders from Simi Valley’s Vista Fundamental School on a special tour of the White House on Wednesday.

The students’ once-in-a-lifetime field trip was not to Washington, however, but across town to the Ronald Reagan Presidential Library. A scale model of the White House has been displayed in preparation for the library’s official opening Monday.

The model, built by Florida craftsman John Zweifel, is a replica of the White House as it was decorated when the Reagans lived there from 1981 to 1988. It measures 60 by 20 feet and stands 4 feet high.

The model offers a cutaway view of the three-story building and includes such details as ringing telephones, working quarter-inch-screen television sets and chimneys that puff smoke.

“It’s really big and really cool,” said 9-year-old Brandon Byer, one of 31 students from Wisteria Street public school who participated in Wednesday’s tour. “I’d love to live in it.”

Classmate Mark Missildine said he was impressed with the mansion’s maze of rooms.

“This is a good place to play hide-and-seek,” he said.

Even Nancy Reagan, who got her first glimpse of the model last week, seemed taken with its authenticity.

“I think it’s extraordinary,” she said. “All these kids are able to see the White House who otherwise might not be able to.”

Many of the students huddled around Reagan throughout the tour, some asking questions--”Do you know Georgie Bush?”-- others offering personal observations--”Oh, how good you smell.”

Reagan, dressed in a green and black checked jacket and a black skirt, took time to answer the children’s questions and shared some of her experiences in the White House.

At one point she stopped to show the children the model’s East Room, which she said was the site of one of her most embarrassing moments as First Lady.

Reagan said that during a concert given by the late classical pianist Vladimir Horowitz she fell off the stage where she had been sitting.

“All I did was change (position) to cross my leg, and I went right over the side onto the floor,” Reagan said, laughing. “Ron said, ‘I told you not to do that unless it wasn’t going well.’ ”

Reagan said she was not hurt.

“I thought I did it rather gracefully,” she said.

Many of the students described Reagan as kind and generous.

“She’s really nice,” Brandon said. “She came out of her way to see us. She didn’t have to, but she did.”

Teacher Pat Huff said the mother of a student is a secretary at the library and helped arrange the tour for the class. However, Huff said her class was not informed until earlier this week that Nancy Reagan would be the tour guide.

She said many of the children’s parents told her that their kids had been so excited that they had trouble deciding what to wear for the occasion. None of the students had trouble getting to school on time Wednesday.