The USDA Farm to School Census found that 44% of schools are engaged in farm to school activities. Furthermore, "farm to school programs exist in every state in the country and the District of Columbia in school districts of all sizes - large and small, rural and urban."
31% of schools are growing edible school gardens. Also, "in addition to buying local products and building school gardens, school districts are promoting locally produced foods at school in general (42%), holding taste tests/demos of locally produced foods (38%), and conducting student field trips to farms (30%)."
"Bringing the Farm to School," United States Department of Agriculture Food and Nutrition Service, accessed August 24, 2015, http://www.fns.usda.gov/farmtoschool/census#/.