Indiana's public schools would be allowed to teach creationism in science classes as long as they include origin-of-life theories from multiple religions under a proposal approved Tuesday by the state Senate.

The Senate passed the bill on a 28-22 vote even though some senators raised questions about the measure's constitutionality. The bill now goes to the House for consideration.

The bill permits local school boards to offer classes that include origin theories from religions including Christianity, Judaism, Islam, Hinduism, Buddhism and Scientology.

Democratic Sen. Tim Skinner of Terre Haute, a former high school teacher, said he believed few teachers would be qualified to teach a class covering multiple religions and worried about the lack of specifics on what such a class would include.

"I think you are just asking schools —and I think you're asking teachers — to do something that is going to open up a door that is probably going to result in a lawsuit which is going to be costly," Skinner said.

Critics argue that the proposal is unconstitutional since federal courts repeatedly have found teaching creationism violates church-state separation because of its reliance on the Bible's book of Genesis.

The original bill simply called for allowing schools to teach creationism, but the Senate on Monday revised it to include references to multiple faiths.

Republican Sen. Dennis Kruse of Auburn, the bill's sponsor, said the U.S. Supreme Court hasn't ruled on the teaching of creationism since the 1980s and that the court could rule differently today. Kruse said he believed the broader religious reference in the bill would improve its chances of being ruled constitutional.

The proposal doesn't require any school district to teach creationism and allows them to continue with their current science classes, Kruse said.

"This does not do away with the teaching of evolution," he said. "This provides another alternative to evolution so our children are being exposed to more than one view, which I think is healthy for them."

Ten Republican senators joined all but one of the 13 Democratic senators in voting against the bill.