St. Patrick taught us that the Trinity is like a shamrock; three parts in one.
Here is a craft that is simple and fun for younger children to make.
Older kids may enjoy it, too.
My daughter, Elizabeth, (age 6) colored and glued the one below:
Print the clover PDF (Free from shop), color the shamrock. Then cut out all the parts. Glue God the Father, God the Son, and God the Holy Spirit, one on each leaf.
For extra fun, tape a real clover into the middle or add glitter!
Hope you enjoy it!