The current issue of Parentwise led me to the National Wildlife Federation's website (nwf.org)  where there is a wonderful article called, "The Dirt on Dirt."  Here is an excerpt: When we let our kids play in dirt we're not only allowing them to explore the
wonders around them, we are also exposing them to healthy bacteria, parasites, and viruses that will inevitably create a much stronger immune system! Many kids who live in an ultraclean environment have a greater chance of suffering from allergies, asthma, and other autoimmune diseases that we would otherwise be protected from through the simple pleasure of playing with some nice common dirt.
 The Joy of Dirt
Studies have shown that simply having contact with dirt, whether it's through
gardening, digging holes, or making pies out of mud, can significantly improve a child's mood and reduce their anxiety and stress. Who knew, right? With antidepressant use in kids on the rise, an increasing number of experts are recognizing the role of nature in enhancing kids' mental health.  Dirt can even improve classroom performance.  It's easy to see the effect when you watch children play outside.
I encourage you to visit their site and get the rest of the dirt on dirt!  I wish I had photos of the Secondary students working with cob mud bricks on Friday to go with this entry.  They mixed up 3 batches of cob with different amounts of sand and clay and left them to harden.  They are working on an outdoor oven on the back porch of the school.  I was less thrilled about the mud slung all over the back (white) wall of the school and the sliding door.  Sometimes I can be a stick in the mud.

I am reading The Nature Principle, Richard Louv's new book.  Something that has stayed with me is this sentence.  "At the University of Michigan, researchers demonstrated the participants' memory performance, and attention spans improved by 20 percent after just an hour of interacting with nature, according to results published in Psychological Journal in 2008."
We spend an hour a day in nature at the Inside Outside School every afternoon, and uncounted hours outside for gardening class, recreation hour, lunch, some outside math classes, and apothecary as well as free time after lunch.  This chapter also states that schools with greened grounds experience reduced absenteeism, something I can attest to.  He is preaching to the choir, but I am loving this book even more than Last Child in the Woods.   More and more I believe in what we are doing with renewed  conviction.  Tom put together our outside classroom benches today on the hillside.  Special learning areas are being tucked away here and there.  Green is beautiful.