Some people have asked for some ideas or traditions to start with their kids that are magically inspired. This tradition is one we started when Leif was 4 or so, and we love it because it is simple, imaginative and nature-based.
On the full-moon your child writes a note or letter to the flower fairies. Outside, in a special spot of their choosing, they make a little flower offering with their letter.
In the morning, they discover that their kind offering has been rewarded with a tiny treasure - perhaps some beach glass, a pendent or a special stone (it is helpful to have a secret stash of these set aside). The flowers are strewn about from all the fairy dancing and the letter is gone.
What's lovely about this particular ritual is that children soon learn to anticipate the full-moon and require no prompting. Just make sure that you are also following along, otherwise you risk missing their offering (should they not remember to tell you they made one).
This activity is not limited to children.