LDS/Mormon Church services are divided into three hour blocks, which used to be in random order for each ward (congregation), but now always have Sacrament Meeting first, if I recall correctly. Here's basically how it goes.
Sacrament Meeting, about 70 minutes:-Call to Attention by a member of the bishopric (bishop and two counselors).
-Opening Hymn and Prayer.
-Organizational announcements (who received what "calling" in the church, and so forth)
-Baby blessings (but not baptisms, we don't have those), if any.
-Sacrament Hymn
-Sacrament (Communion) is taken to members of the ward and any visitors who choose to partake.
-Sermons ("talks) by lay members, usually assigned by the bishopric, but one week a month, we have spontaneous talks.
Closing Hymn and Prayer.
Sunday School (about 50 minutes)-Call to Attention, Opening Hymn (sometimes?) and Opening Prayer
-Teacher gives lesson, talking about some aspect of church history, the Book of Mormon/other scriptures, etc. Audience participation is encouraged. Much like a school lesson, basically.
-Closing prayer.
-Children 5-12 go to Primary instead, which is similar to Sunday School, but for kids. Classes are separated by age group. Nursery for mothers with children under 5.
Elders Quorum/High Priests Quorum and Relief Society (60 minutes)
-Elders are adult men (18 and over) with the priesthood. This is our basic "rank" within the church. High Priests are generally older Elders who have a calling requiring greater spiritual authority, like a bishop or stake president. Relief Society are all women over 18. I can't speak for High Priests or Relief Society meetings, but I am an Elder.
-10 or so minute "Opening Exercises" combining Elders and High Priests, with any announcements being discussed at that time. Opening Hymn and prayer. Split into constituent quorums for the rest of the meeting.
-Similar to Sunday School, assigned teacher gives a lesson, and discusses a particular aspect of the Gospel, of Church History, or of the scriptures, and audience participation happens. We all read from the scriptures if asked to, etc.
-Closing Prayer. We're done.
There are some events that disrupt the three hour block (Ward, Stake, and General Conference), but generally that's how it goes, at least in Utah congregations.
