Jericho Jewish Center  The Jericho Jewish Center (JJC) is a Conservative Jewish congregation located in Jericho, New York. The congregation was established in 1955, when it began meeting on a local private estate. Construction of the Jericho Jewish Center synagogue began June 1959, and completed in 1960.The Iken STEM Science Academy Preschool, housed in the Jericho Jewish Center, opened in 2016.