I'd say that is pretty good for 6, with the materials he has available.
You cannot depict a fully blue sky background in felt pen - if you try to draw on top of it, you get a mucky mess so he has no choice if he wants to show a blue sky, but to end it where he has.
There are lots of details, trees, birds, flowers, grass, animals, water? and a good degree of concentration and patience has gone into that.
On the other hand there is little understanding of perspective and that what you know to be there may not be visible in the pic (so the animals legs are all in a row, rather than the two furthest from the viewer being behind the two closest).
Thats ok, sometimes that takes a while. I'd be impressed he has put in so much work and assuming he wasn't copying a picture and this is all from his imagination (I suspect the pencil drawing above is copied from a picture!), its not at all bad.