wood shed suggestions

hey guys

growing up I had an old wood shed in the back of my parents house, nothing fancy, but it was my fortress, sometimes it was my castle, sometimes it was my army base (and when I grew into my teens, it became a bar, but were not going there now)

anyway, there is a wooded lot behind my backyard, and my 6 year old likes to run around and play in there

ive been thinking for a while it would be cool if he had a little fortress like I used to, so I'm thinking of putting in an 8X8 shed for him

I got my eye on this one
http://www.menards.com/main/prescott-8-x-8-storage-building-kit-only/p-1444432030319.htm
I figured, if I add two 48X48 inch windows on each side that should be plenty of light

apart from actually having this to play in, I intend to make him help me build it and paint it
so hes actually doing something productive this summer


any thoughts, suggestions or ideas?