If you can't go UP with a large enough berm, etc. how about down? What's your water table situation? Can you do a dug out patio/courtyard area for sitting and teaching in?
"The world is changed by your example, not your opinion." ~ Paulo Coelho
Once upon a time there were three bears. And they were visted by a golden haired tiny ad:
Homesteading and Permaculture Bundle - More than 35 Things