For two years, the New York Harbor School has been landlocked in Bushwick, Brooklyn.

Since the public high school opened in September 2003, its founders have gazed longingly eastward toward Governors Island, a site naturally suited for a school whose curriculum centers on the bays and tidal estuaries of the harbor.

On June 20, the school will have an opportunity to seize its future. It will propose, to the city-state agency in charge of redeveloping Governors Island, building a campus on the island facing Buttermilk Channel, the quarter-mile-wide stretch of water separating the island’s former army barracks from Red Hook, Brooklyn.

The campus could mesh seamlessly with another concept to be proposed by the end of business Monday, the deadline set for submission of ideas for development of the island. A group of 55 civic groups called the Governors Island Alliance will unveil its plans for a 6-acre environmental education center, most likely located on the southern edge of the island, replete with a 2-acre reproduction of the New York Harbor, built to scale and ecologically correct with a minibeach representing Jamaica Bay.

How such projects would reconcile with a proposal to build a replica of Shakespeare’s Globe Theater inside a 194-year-old fort will be the task of the Governors Island Preservation and Education Corporation, which has been grappling with how to develop the island since the deed was handed over from the federal government for $1 in 2003.

These proposals are just ideas, two of hundreds Gipec is likely to receive in response to its request for “expressions of interest” by June 20. The public benefit corporation, a subsidiary of the Empire State Development Corporation, sent out 3,000 applications detailing its guidelines, the group’s chairman, Deputy Mayor Daniel Doctoroff, said. Approximately 1,600 applications were downloaded from the organization’s Web site.

“We want people from all over the world giving some thought to appropriate, exciting uses for Governors Island,” he said.

Mr. Doctoroff expressed optimism that scores of for-profit and not-for-profit organizations – potential developers, investors, and tenants – both here and abroad would respond to the call for ideas on how to develop 150 acres of the island. The remaining 22 acres, known as the Governors Island National Monument, will be preserved and managed by the National Park Service.

Though it’s impossible to know how many proposals are forthcoming, real estate experts and those in the planning community are unsure if the private sector will respond enthusiastically to the government’s call, which offers few guarantees compared to a more formal request for proposals.

A master plan designed by architects hired by the city in 2004 was supposed to have led to such a request this year. Instead, the preservation corporation issued requests for more input from the community at large in March. A month later, the group’s president, James Lima, resigned. Those familiar with the situation said Mr. Lima, who helped secure the deed to Governors Island in 2003, was frustrated by a lack of monetary commitment from the city and state. Although the preservation group received $30 million over three years for upkeep and maintenance on the island, as well as an additional $30 million this year for capital improvements, Mr. Lima said at a Community Board 1 meeting in March that it would take at least $80 million to improve the island’s infrastructure – most notably transportation to the island, sewage treatment, and preservation of historic buildings – before private developers would take a risk on developing there.

“The city and state need to make commitments that they will put in money so that the private sector will take this seriously,” the president of Friends of Hudson River Park, Albert Butzel, said. “The problem isn’t that the private sector won’t come up with good ideas, the problem is the more you lay on the back of the private sector to put in infrastructure, the more commercial they have to make it.”

This poses a serious obstacle given the restrictions on the possible uses of the island stipulated by the federal government when it handed the deed over to the state. Of the 150 acres controlled by the city and state, the deed requires 40 acres to remain parkland, of which 20 acres are contiguous; 20 acres must be used for education; and 30 acres must be set aside for “public benefit,” which could include arts and theater groups.

The remaining 46 acres would be available for private development, but that, too, has its restrictions. Developers are not allowed to build residential housing, except dorms and short-term housing such as hotels, nor are they allowed to build for industrial purposes. Gambling in either casinos on the island or riverboats docked there, and power production, are prohibited. Cars, except for maintenance vehicles, are banned from the island.

“It is clearly a site that is so encumbered with public restrictions that it’s very difficult to develop,” the president of the Partnership for New York City, Kathryn Wylde, told The New York Sun. “You’re not going to see a private for-profit proposal that is very aggressive.”

Some money, however, may be forthcoming from the federal government, as $20 million has been earmarked for the island in the fiscal 2006 federal budget. The money, if granted in the budget, will be used to repair 40 docks and install a floating ferry dock to make it easier for private water taxis to take visitors to the island, said Robert Pirani, the director of environmental programs at the Regional Plan Association, one of the lead organizations of the Governors Island Alliance. Mr. Pirani, who knows of at least a dozen plans forthcoming this week from the private sector, acknowledged that once Gipec puts forward the more formal request for proposals, developers will get much more serious and detailed.

“The more specific question you ask, the more specific answer you’ll get,” he said. “Gipec asked for general ideas.”

Until now, ideas from the private sector have included hotels, bed and breakfasts, museums, office space, a marina, and a conference center, one of the first ideas discussed in 2000, during the waning years of the Giuliani administration. At one time or another since then, plans have called for the involvement of the city’s public and private universities, which may be readying their own proposals. One idea backed by Senator Schumer is the creation of a CUNY research facility built around a high-speed computer center that would do advanced modeling for a variety of industries.

A notably different idea may come from the private sector, from a group called Federal Development, based in Washington, D.C., according to a consultant for the company, Michael Fishman. Mr. Fishman, who works for the engineering firm Halcrow, said Federal Development’s proposal would be based on making the island a model of “environmental and economic sustainability.” Mr. Fishman said Federal Development, which, according to its Web site, specializes in “master development of publicly owned real estate assets, “will propose to take on a 99-year lease of the property as the master developer on the island, coordinating individual development projects and helping to secure funding from investors, educational institutions, foundations, and governments.

Such a plan, of course, sounds like what the preservation corporation was created to do in the first place.