Church seders--as opposed to temple seders--are a relatively new phenomenon. They came about as a result of the Catholic Church’s public apology to the Jewish community for continuing the belief that the Jews were responsible for the death of Jesus. Once the Church changed its stance on the Jews in the 1960s, it freed up the Christian world to accept the Jewish life of Jesus. Celebrating Passover would have been his tradition as well.
These seders are either intended to recreate a 2,000-year-old meal and celebration, or are similar to the modern Jewish seder which has foods and discussions that are influenced by millennia of experimentation and interaction with the communities in which Jews have lived throughout the world.
While temple seders are built to retell the story of the Exodus from Egypt, Church seders are usually structured around the story of the Last Supper. Many Christian scholars agree that the Last Supper in the New Testament is a symbolic seder meal. It is there to connect the life, death and resurrection of Jesus with the life, slavery and ultimate freedom of the ancient Israelites. Church seders may also share the rituals of a Jewish Passover seder so that worshippers can experience something like what Jesus may have experienced in his lifetime. These are all goals consonant with Christian theology, but do not create a Jewish Passover seder.
Some organizations create interfaith seders around liberation themes. These are all interesting and worthy uses of the Passover seder format, but are not the same as a Passover seder in a family setting.
The Guide to Passover for Interfaith Families is also available in PDF and Word formats.