A really fun and creative (and a little daring) project for a child at least 4 years old with supervision.  My 7 year old loves to work together with my 4 year old son to make a variety of patterns and pictures by hammering tiny nails through a hole in each piece of wood to attach it to a cork board.  It includes 50 painted wood pieces, a 6" cork board, skinny nails, wood hammer, and suggested picture combinations.  Charlie is very proud when he masters a picture and is starting to make up his own images.  You can substitue wider headed nails or tacks if desired.  Made by Haba in Germany.

Ages 4 and up.  Keep out of reach of young children without supervision.