Child-like vs childish

The problem with gearing the Mass towards children (and we're obviously talking about the Novus ordo here) is that it becomes childish in the worst sense. Worse is the outcome of making the Mass childish: eventually the children grow up and feel that the Faith is something that they can put away, along with other childish things -- as they are now adults. The flipside is that the adults who accompany the children feel foolish doing "childish things" like kneeling, praying, abandoning themselves to Our Lord as these are associated with balloons, facepaint, colouring sheets pinned to the altar cloth, blessing of soft toys, singing "Jesus wants me for a sunbeam" etc. 

And yet ... if we are to embrace Our Lord fully we need to become as a little child. But somewhere along the way this got confused with being childish. To feel genuine humility before the sacrifice at Calvary, to receive the Blessed Sacrament on the tongue whilst kneeling, to open ourselves to the possibilities of God's love -- that is being like a child, without guile, without barriers. How did this get turned into clown Masses and teddy-bear's picnic Masses? 

Were the Apostles childish or child-like in their faith?

I love the following prayer from  St. Alphonse Ligouri's Stations of the Cross, and use it as a penitential prayer at night. It's impossible to say without becoming as a child but impossible to say meaningfully with a childish attitude. Even my 7 year old understands the difference.

I love Thee, Jesus my love above all things; I repent with my whole heart for having offended Thee. Never permit me to separate myself from Thee again. Grant that I may love Thee always; and then do with me what Thou wilt.