There is a strong Biblical call to rest with God, to in be his presence, to accept his giftings, and to receive of his wisdom. Too often it would seem the church becomes engrossed in being an institution rather than what it is called to be. The days of huge Sunday Schools are long gone. The number of children coming to church should be a concern to us all. There are a couple of possibilities.
Some churches run holiday clubs which are a mixture of fun with some basic Christian teaching.
These events need preparation and personnel. Normally they would last a week, perhaps tied into a major festival, such as Easter, or simply a diversion in the summer. There are many schemes available. Other churches, in effect, have Sunday School on a weeknight. This means that many children for whom Sunday would be impossible still have opportunity to gain teaching and insight.