The Most Holy Trinity

"The mystery of the Most Holy Trinity is the central mystery of
Christian faith and life."  
-- Catechism of the Catholic Church. Number 234.

I've been studying the Catechism in preparation for this
Saturday's over-nighter program on the Trinity. The Catechism
numbers starting with 232 are quite profound. I think the name
"Trinitarian" would have been a justifiable alternative to
"Christian" as the name of our religion.

Here's the money quote: "The real distinction of the persons
from one another resides solely in the relationships which 
relate them to one another." (255)

The three persons aren't three gods, or three parts of one god, all
and each one God. In relationship....

Words are truly inadequate. The Trinity is a concept so far 
beyond human thought that revelation is the only way we could
conceive it. It is such an deep mystery that even with
revelaton, the human mind would rather turn away and ignore
the mystery.

How to witness to this truth to children? Flawed but understandable
comparisons (St. Patrick's clover leaf), or abstract theological
terminology that will leave the kids scratching their heads?

The old Baltimore Catechism No. 2 actually has some language that may
be useful:

- Nature (WHAT are you? a human being, God) versus person (WHO are
  you? David, Father/Son/Holy Spirit).

- The Divine Persons are like members of a family EXCEPT that they
  share the unique Divne Nature.

I am imagining a demonstration where I stand two children in front of
the group (or a child and an adult) and quiz the group on their
nature ("What is this?" -> human being) and attributes of that nature
(two arms/two legs, speeks, breathes, eats, sins -> human nature is
common, but with multiple instances) and their personality (age,
height, (origin), !relationships! -> individual). Then contrast with
Divine Nature (What? God, all-powerful, all-knowing, omni-present,
eternal -> unique) and Persons (Who? Father, Son, Holy Ghost,
relationships -> distinct but with single nature).

The question "What does 'person' mean in the context of the Trinity?"
may be meaningless. The word is just a label for this reveled
concept, which is otherwise outside human experience. It draws a
comparison with human personality without defning what a Person is.

Is the meaning of the Trinity that there is in God complexity without 
disorder?