Details about the new sex education curriculum in New York City public schools are out -- and some are concerned the lessons are too racy.

The New York Post obtained workbooks that will be used for the new recommended curriculum, which begins in middle schools and high schools around the city next spring. Parents, they say, may be shocked by details of the work.

Middle school students will be assigned "risk cards" that rate the safety of different activities, the paper says, from French kissing to oral sex.

The workbooks for older students direct them to a website run by Columbia University, which explores topics such as sexual positions, porn stars, and bestiality. The lessons explain risky sexual behavior and suggest students go to stores to jot condom brands and prices.

The Department of Education says the curriculum "stresses that abstinence is the best way to avoid pregnancy and STD/HIV" and reminded the Post that parents have the option to exclude their kids from lessons on "methods of prevention."

When given details of the new programs, one Manhattan mom -- who has a child in middle-school -- was surprised.

"I didn't know how much detail they would get," she said.

In August, Deputy Mayor Linda Gibbs commended the return of mandatory sex ed, saying the DOE wants to give students the correct information about sexual activity if they do choose to engage in it.

"We want to help kids to delay the onset of sexual activity, and if they choose to engage in sexual activity, to do it in a healthy way," she said.

The classes will be coeducational, and can be incorporated into existing health education courses.