Abstract: Each block of a set of wooden blocks bears indicia of the tree species of the wood from which the block is made. Preferred embodiments may include the following features. The blocks are configured as building blocks for children. The indicia on each block show the living tree from which the lumber for the block is derived. The indicia are laser etched upon the blocks. The indicia comprise a picture of a living tree, divided into two portions, one portion showing the tree foliated and one portion showing the tree defoliated. The indicia comprise a picture of a leaf of the living tree, the common name of the tree species and the taxonomic name. The blocks are accompanied by a data sheet further describing the woods and trees of the blocks of the set.