In this message, children will hear the story of Thomas, the disciple who refused to believe in the Resurrection until he saw Jesus himself. Use simple "unbelievable tricks" to introduce the element of doubt and skepticism, and emphasize to youngsters the importance of trusting in God even though we don't physically see Him. Jesus calls those who believe without seeing "blessed"-- that includes us!

https://ministry-to-children.com/wp-content/uploads/2021/04/Doubting-Thomas-Children-Sermon-Lesson-John-20.pdf

https://ministry-to-children.com/doubting-thomas-lesson-john-20

https://ministry-to-children.com/lesson-jesus-alive/

Children tend to be rather trusting in general. However, they are also literal in their understanding and interpretation of things, and often have a hard time grasping abstract or unseen concepts. This message reminds kids that our faith in Jesus is reliable and true, even though we cannot physically see or touch the Lord. When we believe despite a lack of sight, Jesus says that we are considered “blessed”!
Law/Gospel Theme: Jesus most certainly died and came back to life! He appeared to the disciples, and one of them (Thomas) insisted on having proof to believe He was truly alive. We might not have a lot of scientific “evidence”, but we trust in God’s Word and believe that Jesus died and lived for our sake. We know God loves us and we can trust Him for all things.
Optional Materials: Pencil, eraser, white board or paper, water, food coloring (varying materials depending on what “tricks” you wish to use).
Bible Passage: John 20:19-31


On the evening of that day, the first day of the week, the doors being locked where the disciples were for fear of the Jews,[c] Jesus came and stood among them and said to them, “Peace be with you.” 20 When he had said this, he showed them his hands and his side. Then the disciples were glad when they saw the Lord. 21 Jesus said to them again, “Peace be with you. As the Father has sent me, even so I am sending you.” 22 And when he had said this, he breathed on them and said to them, “Receive the Holy Spirit. 23 If you forgive the sins of any, they are forgiven them; if you withhold forgiveness from any, it is withheld.”
24 Now Thomas, one of the twelve, called the Twin,[d] was not with them when Jesus came. 25 So the other disciples told him, “We have seen the Lord.” But he said to them, “Unless I see in his hands the mark of the nails, and place my finger into the mark of the nails, and place my hand into his side, I will never believe.”
26 Eight days later, his disciples were inside again, and Thomas was with them. Although the doors were locked, Jesus came and stood among them and said, “Peace be with you.” 27 Then he said to Thomas, “Put your finger here, and see my hands; and put out your hand, and place it in my side. Do not disbelieve, but believe.” 28 Thomas answered him, “My Lord and my God!” 29 Jesus said to him, “Have you believed because you have seen me? Blessed are those who have not seen and yet have believed.”
30 Now Jesus did many other signs in the presence of the disciples, which are not written in this book; 31 but these are written so that you may believe that Jesus is the Christ, the Son of God, and that by believing you may have life in his name.
-John 20:19-31