The Museum Branch continued to accept occasional outside requests for exhibit design and construction on a reimbursable basis. It was asked to do the exhibits for a new museum in the Prehistoric Indian Mounds State Park at Marksville, Louisiana. Floyd LaFayette guided this job through to completion, establishing excellent working relationships with Louisiana State Parks director William Wells, who later became a Park Service official, and archeologist John A. Ford of the American Museum of Natural History, who served as curatorial expert. Installation of these exhibits in February 1954 led to a second allotment of $10,000 in state funds for additional work on the Marksville museum. Carnifex Ferry State Park in West Virginia also obtained museum exhibits designed and prepared by the laboratory, this work extending from mid-1954 into early 1956. From the Marine Corps came a request in 1954 to prepare a diorama as part of a special exhibition on naval history in the National Museum's Arts and Industries Building. The rather complex group illustrated in miniature the latest tactical methods for a combined amphibious and airborne assault on a fortified beach. Again satisfaction brought more work: the Corps ordered eight copies to circulate as traveling exhibits.

For a new hall of American Indian ethnology the National Museum contracted with the laboratory to prepare a small diorama showing the interior of a kiva. Before its completion in early 1955 the museum provided $2,000 more for a second group to depict an Inca farming scene. The laboratory's newest preparator, Russell J. Hendrickson, painted the background for it with a fresh and expert touch. Other reimbursable projects during 1955 included updating the National Capital Park and Planning Commission's large model of central Washington, preparation of the Interior Department's portion of a major federal traveling show, "The American Dream," that circulated to department stores in fifty cities, and a set of attractive botanical panels Buffmire painted for the Garden Club of America's national headquarters. Installation of exhibits prepared for the St. Augustine Historical Society in April 1956 and of the second Marksville unit in July allowed the branch again to concentrate its production resources on national park museums.

When the 1955 fiscal year began, the Museum Branch faced what seemed then a very heavy but promising schedule. Congress had appropriated funds for four new park museums. One would serve Carlsbad Caverns, two would supply pressing needs at Colonial National Historical Park, and the fourth would replace dangerously combustible and inadequate facilities for Grand Canyon. The state of North Carolina had already provided money for the Park Service to build a museum beside the Blue Ridge Parkway.34 The branch would need to keep pace with architectural planning and construction on all these buildings, but the Blue Ridge project had the earliest completion date.

North Carolina wanted to interpret its mineral resources to the public. In return for initial funding the Service undertook to develop and operate the Museum of North Carolina Minerals as a focal point of interest along the parkway. The Museum Branch planned exhibits on the minerals occurring in North Carolina that were or had been important in the state's economy. Specimens supported by graphics would show each mineral, tell something of its occurrence, extraction, and processing, and illustrate its uses.

Floyd LaFayette, who played a leading role throughout the project, developed the layouts with strong curatorial support from Bennett T. Gale, geologist in the Natural History Branch. When they presented the plan to a sponsoring group of North Carolinians, the response was distinctly unfavorable. Members of the group were ardent mineral collectors who had envisioned the museum as an array of fine specimens displayed for their aesthetic appeal. The plan included only a few such exhibits but called for an adjacent study collection room equipped with well-filled specimen cabinets, maps of mineral sites, and reference books as a rendezvous for students and collectors. The Museum Branch argued the merits of its concept and Ben Gale persuaded the state to accept it. The museum opened in June 1955.35 Although mineral collectors were not wholly reconciled, the study collection room received considerable use until staff cuts reduced its availability.

Congressional appropriation for the Grand Canyon museum marked the culmination of Louis Schellbach's long, determined effort to persuade those in authority that the park's rich collections constituted a resource too valuable to keep in an old frame schoolhouse. Schellbach had conceived concrete plans for the museum. He knew just where he wanted it and had many ideas for its interpretive content. At the same time, the Service reached a farsighted decision to divert future development from the canyon rim, upon which too many structures already intruded. The museum would be part of the new scheme. The change of location disappointed Schellbach so deeply that he lost heart for the enterprise, leaving its planning largely in the hands of the Museum Branch by default.

Design and Construction chief Tom Vint visited Grand Canyon in July 1954 to go over the proposal as it affected the museum. Cecil Doty, architect for the museum, accompanied Vint to the conference and began preliminary floor plans on the spot. Characteristically Vint also included Ralph Lewis in the party to ensure close collaboration between architect and museum planners from the start.36 Museum Branch representation helped to make certain that the building included a large, secure room of fire-resistive construction for the study collection as well as suitable exhibit space.

Exhibit planning, which began in earnest a year later, marked a turning point in Museum Branch practice. Before World War II, it may be recalled, curators prepared the entire exhibit plans including layouts, then turned the completed specifications over to the preparators for production. In the intimate working conditions of the postwar laboratory, curators and artists tended to consult each other at earlier stages. Outside the Park Service such innovative installations as the Warburg Hall at the American Museum of Natural History exemplified a contemporaneous inclination among museums to place more emphasis on design. A continuing debate developed over the respective roles of curator and designer, fueled by a perception that professional designers were insensitive to the scholarly value of museum objects.