Sunday school is a Christian educational institution for  children and young people.
I know it as Adult Bible study for the adults
I see. Seventh-Day Adventist and other sabbatarians hold their schools on Saturdays.
 Sunday Schools were first set up in the 1780s in England to provide education to working children
Correct, and they aim to teach kids reading, writing, and arithmetic with a knowledge of the Bible.
By 1785, 250,000 English children were attending Sunday School. That's a lot of kiddies !
wrote an article in his journal, and as a result many clergymen supported schools, which aimed to teach the youngsters reading, writing, cyphering (doing arithmetic) and a knowledge of the Bible.
In 1785, 250,000 English children were attending Sunday school. There were 5,000 in Manchester alone. By 1835, the Society for the Establishment and Promotion of Sunday Schools had distributed 91,915 spelling books, 24,232 Testaments and 5,360 Bibles. The Sunday school movement was cross-denominational. Financed through subscription, large buildings were constructed that
Sunday school
A Sunday school is an educational institution, usually (but not always) Christian in character. They were first set up in the 1780s in England to provide education to working children. Today, "Sunday school" has become the generic name for many different types of religious education pursued and conducted on Sundays by various denominations.
William King started a Sunday school in 1751 in Dursley, Gloucestershire, and suggested that Robert Raikes start a similar one in Gloucester. Raikes was editor of the Gloucester Journal. He