Here are a couple of excerpts from the chapter, "Out of Door Life For The Children" in Charlotte Mason's Home Education:
"...every hour spent in the open is a clear gain, tending to the increase of brain power and bodily vigour, and to the lengthening of life itself..."(p.42)
"Get the children to look well at some patch of landscape, and then to shut their eyes and call up the picture before them, if any bit of it is blurred, they had better look at it again."(p.48)
(on observing flowers)"The flowers, it is true, are not new;but the children are;..."
"Never be within doors when yo can rightly be without." ((p. 42)
"In the first place, do not send them(outside);if it is anyway possible, take them; for although the children should be left much to themselves, there is great deal to be done and a great deal to be prevented during these long hours in the open air." ((p.43)