The poem
Piping down the valleys wild, Piping songs of pleasant glee, On a cloud I saw a child, And he laughing said to me:
'Pipe a song about a Lamb!' So I piped with merry cheer. 'Piper, pipe that song again;' So I piped: he wept to hear.
'Drop thy pipe, thy happy pipe; Sing thy songs of happy cheer!' So I sung the same again, While he wept with joy to hear.
'Piper, sit thee down and write In a book that all may read.' So he vanish'd from my sight; And I pluck'd a hollow reed,
And I made a rural pen, And I stain'd the water clear, And I wrote my happy songs Every child may joy to hear.

Sweet, simple...everything that the child asked, the piper did. The child reacts the way one would hope young children would during circle time--or story time. Stories should entertain, and tap into the emotional levels. The child disappeared (perhaps an angel), the the piper takes on the role of a writer. It's a nice switch from the oral tradition of story telling, to the recording (printing press) version of sharing stories.
In some ways, one could also interpret the scene as listening to what a child says. A child is happy with simple things, done with the heart.