NEW CITY — A former suburban prosecutor and PTA president had sex with two underage boys, joined many other teens in booze and pot parties, and kept it all a secret from her police chief husband, officials said yesterday.

Beth Modica, 44, was indicted on 35 counts alleging statutory rape, criminal sex acts, sex abuse, and endangering children. She pleaded not guilty at her arraignment in Rockland County Court. Hours later, she posted $75,000 bail and was released pending a court appearance next week.

“These are serious charges, against children in her community,” Judge Catherine Bartlett said. She issued orders of protection for the two boys involved, whose names were not made public.

The district attorney, Thomas Zugibe, said Mrs. Modica had intercourse and oral sex with a 16-year-old boy and oral sex with a 15-year-old boy last summer, and on several occasions served and shared alcohol and marijuana with “many” other teens from Suffern High School at her Sloatsburg home or in her car. She was an assistant district attorney in Queens and Rockland in the 1980s and ’90s. Until this month, she was attorney for the town of Ramapo and the village of Sloatsburg.