What are the key subjects to teach children in Sunday school?

According to Spurgeon, there are five critical subjects for Sunday School teachers to impart to children: 1) Morality, which teaches the importance of right conduct; 2) Godliness, emphasizing constant belief in God's oversight; 3) The evil of sin, which highlights the consequences of wrongdoing; 4) The necessity of a changed heart, illustrating the importance of repentance; and 5) The immeasurable blessings of being a child of God. Each subject is woven into the fabric of biblical teaching and is tailored to shape children's understanding and character in alignment with God's Word.