Neat-o! The red and green boards are just painted plywood sheets?
Where did you get the plans? We'll be needing a bed for Vlad, eventually; the four brothers are already in bunks.
Yes. The horizontal sheets are 3/4" ply. The vertical pieces are 3/8", and used for shear (is structural terms) to keep the frame from wobbling.
The plan came from a book of kids bedroom ideas. Durn book is MIA in my study.