"When we plant trees, we plant the seeds of peace and seeds of hope." - (Prof. Wangari Maathai, 2004 Nobel Peace Prize Laureate)

Here is a unicef link that aims to promote food security.  http://thegreatnzedibleschoolgarden.wikispaces.com/Fruit+Bearing+Trees
  It has a section where schools can add their own garden stories to the wiki pages.  Lots of good content for learning about food security.