Laura Murphy of Fairfax County, Va., lobbied for legislation that would require teachers to warn parents about books containing sexually explicit material, including Toni Morrison’s “Beloved.” (Jahi Chikwendiu/The Washington Post)

It wasn’t easy to find 22 copies of “Beloved” and “The Bluest Eye.”

But a government watchdog group said lawmakers should read the novels by Nobel laureate Toni Morrison before they vote on a bill that would allow parents to block their children from reading those and other books with sexual content in school.

And so Anna Scholl, executive director of left-leaning Progress Virginia, had the books delivered to the Richmond offices of 21 Republican senators and one Democrat she said probably will favor the bill.

“I think senators should be educated on the subject they’re voting on,” she said.

Supporters of the measure say it gives parents control over their children’s exposure to mature themes. Opponents say it could lead to book banning.

The full Senate was scheduled to vote on the bill Monday but postponed action. If successful it would be the first law of its kind in the country, according to the American Library Association, which tracks such legislation.

The bill would require K-12 teachers to identify classroom materials with “sexually explicit content” and notify parents, who would have the right to “opt out” their children and request alternative material.

Sen. David R. Suetterlein (R-Roanoke), who graduated from a Fairfax County high school in 2003, said the bill amounts to a simple syllabus requirement.

“There are hundreds, probably thousands of books that are assigned to students each year across the commonwealth,” said Suetterlein, who voted for the bill in committee. “I won’t have an opportunity to read every single book that’s assigned, but I think it makes sense that parents know what’s assigned.”

Six Republicans declined the novels from Scholl, citing a no-gifts policy. They include Sen. Stephen D. Newman (R-Lynchburg), chairman of the Education and Health Committee, which advanced the legislation last week and Sen. Charles W. Carrico Sr. (R-Grayson) who has said he had not read “Beloved” but based his opposition on explicit excerpts he has read, which he called “evil.”

The legislation was prompted by a Fairfax County mother who objected to her son, then a high school senior, reading “Beloved” in his Advanced Placement English class. She cited “Invisible Man” by Ralph Ellison and “The Road” by Cormac McCarthy as other examples of books that are inappropriate for students.

The proposal was among a block of uncontested bills passed unanimously by the House last month without any debate — an indication that lawmakers may have been unaware of the potential for controversy.

A spokesman for Gov. Terry McAuliffe (D) has declined to say whether he would veto it.

Del. R. Steven Landes (R-Augusta), chairman of the House Education Committee, sponsored the legislation at the request of House Speaker William J. Howell (R-Stafford).

The National Council of Teachers of English and National Coalition Against Censorship oppose the bill.