The "pre-packaged" bankruptcy would give control of Houghton Mifflin to its lenders.

It comes as cash-strapped state and local governments defer or cancel education-related purchases, reducing demand for textbooks for students from kindergarten to 12th grade.

Traditional book publishers also face pressure from the online availability of published material, including e-books.

Houghton Mifflin has a 41 percent market share in the K-12 educational material and services sector, and its education business accounts for about 90 percent of revenue.

The Boston-based company lost $2.18 billion last year, including a $1.67 billion writedown, as net sales fell 14 percent to $1.3 billion.

Houghton Mifflin and two dozen affiliates filed for protection in U.S. bankruptcy court in Manhattan.

In a court filing, general counsel William Bayers said the reorganization has support from 90.3 percent of creditors and 76 percent of equity investors eligible to vote.

Houghton Mifflin expects to emerge from bankruptcy by June 30. The company said it has $2.68 billion of assets and $3.54 billion of liabilities, and employs 3,300 people.

With a history dating to 1832, Houghton Mifflin said its products serve 60 million students in 120 countries.

The company also publishes the "Curious George" and J.R.R. Tolkien's "Lord of the Rings" children's book series, and games such as "Where in the World is Carmen Sandiego?"

Houghton Mifflin also agreed in January to distribute titles from an Amazon.com Inc publishing unit.

The restructuring is Houghton Mifflin's second in 2-1/2 years. In February 2010, Houghton Mifflin recapitalized its balance sheet with $650 million of new equity capital. That restructuring was out-of-court and did not involve a bankruptcy filing.

Its investors include the investment firm Guggenheim Partners and hedge fund manager John Paulson's firm Paulson & Co., which each holds a board seat.

Paulson & Co., Apollo Management Holdings LP and Marc Lasry's distressed debt firm Avenue Capital Group were among members of a creditor group that negotiated the reorganization.

Houghton Mifflin plans to convert its bank and bond debt into a 100 percent equity stake in a reorganized company, saving $250 million in annual cash interest costs.

Trade creditors and unsecured creditors would be paid in full. Shareholders who back the plan could receive warrants for up to 5 percent of the equity in a reorganized company.

The company has lined up $500 million in financing from Citigroup Inc. It hired Blackstone Group LP and the law firm Paul, Weiss, Rifkind, Wharton & Garrison to provide financial and restructuring advice.