Richard Shilling on Land Art for Kids what a great idea for outside leaf/nature sculptures. make sure to watch an andy goldsworthy documentary too! Should you appreciate arts and crafts you really will really like this site!
Tree Track: Learning About Trees with Wooden Train Tracks @ Play Trains! Kids learn about art, biology, and planning and executing a project while playing with trains. Based on the art installation, "Tree Track", by Christien Meindertsma.