Charlotte Mason quotes William Wordsworth's poem "Intimations of Immortality from Recollections of Early Childhood " on p. 11 of Volume I, Home Education. The context of this quote is that children are not simply "a tablet to be written on, a twig to be bent or wax to be molded. No, they are so much more than that. As we will see from the poem below, they belong to a higher estate than ours.
Note: The above quote is an excerpt from the poem in its entirety. You can find Wordsworth's full ode here.