RAMALLAH, West Bank — Do Palestinian school textbooks "teach terrorism," as Newt Gingrich claimed in a recent debate among U.S. Republican presidential hopefuls?

His example — that Palestinians "have text books that say, 'If there are 13 Jews and nine Jews are killed, how many Jews are left?'" — is not in any of the texts, researchers say.

As for Gingrich's broader claim, the textbooks don't directly encourage anti-Israeli violence, but they also don't really teach peace, studies say.

A review of some texts by The Associated Press, as well as several studies by Israeli, Palestinian and international researchers, found no direct calls for violence against Israel. However, the books lack material about the historic Jewish presence in the region and scarcely mention Israel and then mostly in a negative way. Peace with Israel rarely comes up. Texts for religious schools are harder-core, openly glorifying martyrdom.

Researchers disagree sharply in their interpretation of the material.

Two NGOs, one Israeli and one international, support the view of Israeli officials that the texts promote hatred of Israel. For example, Israel is not included in a list of the countries of the Levant, and Hebrew writing was removed in a depiction of a stamp from British Mandate rule of the Holy Land.

A joint Israeli-Palestinian study takes a softer view, saying that there is no direct attempt to delegitimize Israel, but that "the way and contexts in which Israel is presented may give rise to the impression of an implicit denial of its legitimacy."

The books must be seen in the context of ongoing conflict, said Nathan Brown, a George Washington University political scientist who has written about the issue. While highly nationalistic, government texts don't glorify violence, explicitly deny Israel's right to exist or portray Jews as villains, he said.

"I think the textbook critics have cause and effect mixed up — when there is a viable political process it may be possible to introduce a process to revise the books in a reciprocal way," Brown said.

The argument looms large in a debate driven by the Israeli government, which frequently accuses the Palestinians of incitement in their schools.