This has been a lenten tradition at our home since the oldest children were little. We make Jesus' crown of thorns on a big piece of paper. Then, when someone does a secret good deed, makes a sacrifice, says a prayer, or chooses to follow Jesus instead of listening to self, they put a flower on one of the thorns.
Our usual flowers were drawn in crayon, marker or colored pencil. This year we added a bit of creativity to the devotion. We had a surplice of tissue paper from a baby shower. We cut little squares of the tissue, and then wrap them around the eraser end of a pencil. Put a dab of glue on the end of the thorn, and stick the tissue flower (still on the pencil) to the glue. Remove pencil, and you have a 3-D flower. My children love this.
We hang this in the school room where even little people can access it to make it bloom with their little quiet good deeds. Keep the flower supplies nearby and by the end of lent, Jesus' crown of thorns will be turned into a beautiful crown of flowers, all loving deeds done for love of Him.