Utah finally cashed in Saturday on school trust lands set aside at statehood for the benefit of its schoolchildren.

Shortly before noon Saturday, President Clinton signed into law the Utah Schools and Land Exchange Act, finalizing a land-and-cash swap proposed in May by Gov. Mike Leavitt and Interior Secretary Bruce Babbitt.The federal government is now the new and proud owner of 376,739 acres of former Utah school trust lands - mostly isolated pockets of property surrounded by land it already owns.

The state, meanwhile, is the equally pleased recipient of $50 million and more than 139,000 acres of mineral-rich land that Utah and federal officials believe could be worth up to $1 billion in time.

The trust land was originally intended to raise money for Utah's schools, but the state has realized little benefit over the years because much of that land has been inaccessible for development. The state has been trying for decades to work out an agreement that would free up the land.

Here is what was exchanged:

- Utah will give the federal government 376,739 acres of school trust lands, including rock art in Dinosaur National Monument, the Eye of the Whale Arch in Arches National Park and Lake Powell's Jacob Hamblin Arch.

- The federal government will give Utah a check for $50 million and more than 139,000 acres of land located throughout the state containing coal, natural gas and other minerals that could be developed or leased.

Sen. Bob Bennett, R-Utah, said the deal is significant not only because it will generate millions for Utah schools but because it could pave the way for similar land exchanges that could bring in millions - if not billions - more for Utah schools.

"This should be a model for future land swaps because there are still hundreds of thousands, if not millions, of acres of school trust land out there for which the school kids are not getting any revenue," Bennett said Saturday afternoon.

"This is simply recognizing the Constitutional right given to Utah at the time the state was formed and making it possible to do what has been anticipated for over 100 years."

Leavitt said Saturday's signing culminated "a remarkable and historic series of events that will result in . . . millions of dollars of benefit that will continue in perpetuity."

The deal also was aimed at softening the blow many state officials felt Utah took two years ago when Clinton created the Grand Staircase-Escalante National Monument. The president referred to the monument in statements he made from the Oval Office before signing the bill.

"I made a promise to work to ensure that Utah's schoolchildren, the beneficiaries of the state trust holdings within the monument, would in fact benefit from, and not be harmed by, the establishment of this national showcase," the president said.

"I am proud to say we have kept our promise. We have delivered more, and in a shorter time, than perhaps anyone believed possible."

Bennett said he credits Babbitt and Leavitt, not Clinton, for orchestrating the deal.

"I don't think he (Clinton) knew anything about the land swap before they handed him the bill and told him to sign it," Bennett said.

Mickey Ibarra, a Utahn who serves as director of intergovernmental affairs on Clinton's White House staff, agreed with Bennett that the land swap could set a precedent.

"It's the biggest state-federal land exchange in history and, we estimate, will have a $1 billion benefit to Utah schoolchildren over 30 years," said Ibarra, who witnessed the signing Saturday.

"It is a very good example of leaving politics at the schoolhouse door . . . and working in partnership to benefit Utah public school children."

Ibarra credited Leavitt and members of the state's Congressional delegation for working with the administration to end the long battle over use of state trust lands.

Environmental groups approve of the swap because it prevents lands inside federal parks, monuments and forests from being developed, drilled or mined.

"To my knowledge there is not a single conservation group that has opposed this agreement. . . . We're huge fans," said Tom Price of the Southern Utah Wilderness Alliance. "This agreement is a great example of how people on different sides can come together and resolve a dispute."

The Utah School and Institutional Trust Lands Administration, which will manage the land and the revenue it generates, has said it would drop its lawsuit challenging Clinton's creation of the Grand Staircase-Escalante National Monument once the land swap became final.

The bill was held up in Congress for months by Sen. Dale Bumpers, D-Ark. Bumpers threatened to filibuster the land swap unless Utah's Congressional delegation supported his effort to create a historic site in Little Rock honoring the Brown vs. Board of Education Supreme Court decision that ended the segregation of public schools. He withdrew that threat after his bill passed the House earlier this month.