Sunday Schools weren't part of 1st century worship...... thus the WTS doesn't.
WTCD:
*** it-2 p. 876 School ***
No separate arrangement for children, as with the modern-day “Sunday school,” was anywhere authorized or practiced by the Jews or by the Christian apostles.
*** w90 8/1 p. 3 Young People Who Serve God ***
In most of the 60,000-and-more congregations of Jehovah’s Witnesses throughout the earth, you will find many young people. They do not go to a weekly Sunday school or catechism class. Rather, these young people benefit from and even participate in congregation meetings. Little ones may offer simple comments. Preteens participate in the Theocratic Ministry School. Many teenagers spend school vacations helping neighbors to learn about God and his marvelous promises for the future.
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