The National Endowment for the Humanities has awarded Arena Stage $500,000 to pay for specialized explanatory materials for adult and student theatergoers.

The endowment announced yesterday that it was giving 10 cultural institutions funds to strengthen their activities in the humanities. Arena was the only theater selected.

Stephen Richard, Arena's executive director, said the money will enable the theater to reinstate background pamphlets called performance journals. The theater stopped producing the journals two years ago when a foundation grant ran out.

The journal "gets at the ideas and backgrounds of plays" by talking about the era in which the play was written, how it fits into the body of the playwright's work and how it is assessed by scholars. "It connects the work, such as 'Long Day's Journey Into Night,' to the scholarly trends in the humanities," Richard said.

Explanatory materials are distributed to adults and students. Nearly 20,000 students attend plays at Arena each year. The theater spends about $1.1 million a year on community engagement, its catchphrase for education work with teachers, students and the general audience. That amount includes a loss on student tickets, which are sold at a discount, Richard said.

Arena will use the money to expand its work with teachers by developing more curriculum-based materials. "What we will do more of will be convening teacher groups so that we can train teachers to use the materials and then have the show experience serve their needs," Richard said.

The NEH grant has to be matched at a 3-1 ratio by private funds. Richard said he was optimistic because these programs have a special appeal. "This is an area that has a great deal of enthusiasm from our donors," he said.