The Saudi Embassy has mailed out more than 5,000 padded envelopes -- bulky with videos and books about Islam -- to schools nationwide in the last few weeks. But the schools, upon receiving the unexpected packages, have been unsure about the mailings and, in some cases, have even called the FBI to ask whether they are safe to open.

The packages, which had return addresses marked, "Prince Bandar Bin Sultan, Royal Embassy of Saudi Arabia," included a two-part PBS video called "Islam: Empire of Faith," Karen Armstrong's book, "Islam: A Short Story," and a Saudi-produced publication, "Understanding Islam and the Muslims."

Jim Rice, supervisor of one of the counterterrorism squads for the FBI's Washington Field Office, said he got calls from about a dozen area school officials asking about the packages. FBI officials said they inspected the large manila envelopes and found they contained nothing of harm.

"We told everyone that the Saudi mailing was professionally done and there was nothing to worry about," said Rice. "We did say that if the packages included wires or had been opened and then resealed, then that was cause for concern. But other than that, they are fine." The FBI sent an e-mail to schools addressing the concerns.

Saudi Embassy officials said the packages, which were sent to more than 100 schools in the Washington region, were meant to inform the public about their faith and dispel rumors or stereotypes after the Sept. 11 attacks, said Sherry Cooper, secretary to the ambassador.

"We also got some calls asking us what this was. I know these are terrible times, with the anthrax scares," said Cooper. "But if they were going to freak out with the Saudi Embassy address, then they would freak out if we called ahead or sent a letter ahead. I didn't feel like we could really win."

Cooper said that the mailings were meant to be a proactive attempt to be open about Islam and provide educational materials for schools in the United States. She said she picked schools at random in each of the 50 states.

"The American Muslim community have been under attack and a backlash," Cooper said. "And we wanted this to educate people about Islam and the Muslim faith and promote tolerance."

Some school principals said that they already had some of the materials, but that they were curious about why they were getting a package from the Saudi Embassy.

When the package arrived at Frederick High School just after New Year's, Principal Denise Fargo-Devine was worried that an impostor was using the embassy's return address. So she called to verify.

"It was bulky, especially from the two-part video. I had no idea what it might or might not be. The package didn't really look diplomatic or official, aside from the return address," she said. "I don't want anything reflecting negatively on our embassies."

Now the materials are shelved in the library, and the school's social studies teachers are considering whether to incorporate them into the curriculum.

School officials in Fairfax and Montgomery counties said they were reviewing the materials to see if they could add them to their social studies curriculum.

At Annandale High School, the principal displayed the mailings in the school's media center.

"I saw no reason not to," said Donald Clausen, the school's principal. "We have about 200 or 300 kids here who are Muslim and I thought this was basic information and a nice idea."

Other school principals, at some of the region's more diverse schools, said they weren't surprised to get the package.

The mailing arrived last week without any scrutiny at High Point High School in Beltsville, Principal William H. Ryan said.

"Those type of things don't make us bristle. We're one of the most diverse schools in the state, with 72 languages spoken and 50 countries represented," said Ryan. "And we've also been very sensitive since September 11 about not making people of other religions feel uncomfortable."