The Carnegie Museums of Pittsburgh are in the home stretch of a $150 million fund-raising drive to help pay off a major dinosaur hall expansion, new educational facilities and other long-term museum improvements and investments.

Museums President David Hillenbrand told a group of board members, donors and trustees last night that $118 million, or 79 percent, of the goal already has been reached, with hopes to complete the fund raising in 12 to 18 months.

The largest chunk of private financing came from the Hillman Family Foundations, which donated $12.8 million.

Museum visitors will notice the improvements late next year when touring the $36 million Dinosaurs in their World exhibition at the Carnegie Museum of Natural History, displaying the world's third-largest dinosaur fossil collection.

The museums will revamp the educational spaces at the Oakland home of the natural history and art museums at the same time with the construction of a new Center for Museum Education at the site. It will take visiting school buses off busy Forbes Avenue -- reorienting them to a back entrance -- and reorganize the confusing collection of classrooms at the old building.

The center will allow the museums "to consolidate our educational facilities in one area. This is a huge complex. Most of our classrooms are underground here or way up on the third or fourth floor," Mr. Hillenbrand said yesterday. "When you have people in classroom situations they're dispersing through this labyrinthine building -- this allows us to put our primary learning facilities in one place."

Plans are for all four Carnegie Museums -- the two in Oakland, plus the Andy Warhol and the Carnegie Science Center -- to use the educational facilities and cooperate on programming, Mr. Hillenbrand said.

The capital campaign also will support the eco-friendly expansion of facilities at the Powdermill Nature Reserve in Westmoreland County; pay off the 2003 renovation of the Scaife Galleries at the Museum of Art; boost general endowment funds; and pay for behind-the-scenes infrastructure improvements at museum buildings.

The current capital campaign was launched in 2002, but was announced publicly last night. The last Carnegie Museums capital drive ended in 1995.

Other funding for the capital drive has come from state government, the Heinz Endowments, R.K. Mellon Foundation, Eden Hall Foundation, R.P. Simmons family, Buhl Foundation and the Carnegie Museum of Art Women's Committee.