I believe this very sweet old handmade secretary style desk was made of cigar box wood, or wood from an old crate, as there is some text showing through the green paint on the back side. Everything about this makes me happy, teeming with the vision of some father or grandfather carefully piecing it together for a much loved child. 

4 5/8" t x 4 3/16" w x 2 7/8" d. Varnished and green painted wood. Very good condition. It looks like perhaps tiny screws or nails were initially used to join sides then abandoned in favor of glue.