That's right my dear @rodrook , 3 years old is the appropriate age for children to start in this wonderful sport.
I started my nephew when he was 7 years old and he managed to advance to the point that when he was 9 years old he won a tournament and also beat him in a simultaneous that was offered to the children.
I had a community chess school and its members gave me a lot of satisfaction in the different participations they made.
Thank you for sharing your interesting program.