This article is about adding a school garden for your classroom. I think that this would be an easy thing to implement in a school, and it would also be educational for the students in how to grow certain fruits and vegetables.
School Garden Wizard: Create the Garden: Designing the Garden
The benefits of school gardens are numerous and are not restricted to a particular age group. Gardens can accomodate students visual, auditory and kinesthetic learning styles. (PDF format only) - Our Secret Garden