Montessori and Religious Education of the Child
"Godly Play: An Imaginative Approach to Religious Education" by Jerome W. Berryman
"Young Children and Worship" by Sonja M. Stewart and Jerome W. Berryman
"Teaching Godly Play: The Sunday Morning Handbook" by Jerome W. Berryman
"I Wonder...More Bible Stories for Children and Worship" by Janet Schreuder
"The Religious Potential of the Child" by Sofia Cavalletti
"The Spiritual Life of Children" by Robert Coles
And a video, "Discovering the Real Spiritual Life of Children" with Sofia Cavalletti and Silvana Montanaro.
A good description by Faith at Home, "Berryman developed his Godly Play approach after training under Sofia Cavaletti, who developed the Catechesis of the Good Shepherd. CGS is yet more Christ-centered and sacrament-focused, and less story-oriented, than Godly Play. CGS takes place in an atrium, requires more significant training of the catechists, and is more similar to classical Montessori education than Godly Play often is, in practice. Perhaps this is the other end of the spectrum from Young Children & Worship."