A retired New Jersey school teacher, arrested last fall in a crackdown on an interstate pornography ring, pleaded guilty in Circuit Court yesterday to committing sex acts with three teen-age boys.

Richard Pepe, 48, of Elizabeth, N.J., faces up to 30 years in prison for his conviction on three counts of unnatural and perverted sex practices.

He will be sentenced Oct. 24 by Judge Raymond G. Thieme Jr.

Between May 1992 and Aug. 2, 1993, Pepe committed sex acts with boys who were 14 and 15 years old. The crimes occurred at the Red Roof Inn on Route 170 near the Baltimore-Washington International Airport in Linthicum.

The victims were part of a group of about 15 boys, ages 8 to 15, who were recruited from skating rinks and other teen-age hangouts in Baltimore and northern Anne Arundel County, police said.

The boys were filmed committing sex acts. At least 10 boys were paid $250 a day to participate, police said.

Police said Pepe and Eric Nastelin, 32, of Bound Brook, N.J., helped produce the pornographic videos. Mr. Nastelin is awaiting trial.

John G. MacLeod, 62, of the 8100 block of Eastern Ave., Silver Spring, pleaded guilty earlier this year to sex offenses in connection with the pornography ring.

He is scheduled to be sentenced tomorrow in Montgomery County Circuit Court, where his case was transferred.