A Sunday school is an educational institution, usually Christian in character and intended for children or neophytes.
Sunday school, Indians and whites. Indian Territory (Oklahoma), US, c. 1900.
Sunday school at a Baptist church in Lejunior, Harlan County, Kentucky in the United States, 1946.
Baptist Sunday school group in Amherstburg, Ontario, [ca. 1910]
A church service is a formalized period of Christian communal worship, often held in a church building. Most Christian denominations hold church services on the Lord's Day ; a number of traditions have mid-week services, while some traditions worship on a Saturday. In some Christian denominations, church services are held daily, with these including those in which the seven canonical hours are prayed, as well as the offering of the Mass, among other forms of worship. In addition to this, many Christians attend services on holy days such as Christmas, Ash Wednesday, Good Friday, Ascension Thursday, among others depending on the Christian denomination.
A Lutheran Divine Service in the United States
A Catholic Mass at St. Maria Church, Sehnde, Germany, 2009
Depiction of early Christian worship in the Catacomb of Callixtus
A Pentecostal worship service at Dream City Church, affiliated with the Assemblies of God USA, in 2007, in Phoenix, United States