@littlek,
If you get at least 4-5 hours of sun you can try:
Salad Greens- such as leaf lettuce, arugula, endive, cress, and radicchio; also broccoli, cauliflower, peas, beets, brussels sprouts, radishes, swiss chard,
leafy greens- such as collards, mustard greens, spinach, and kale,
plus most beans.
Sage will not be happy with shade. It wants full hot sun - picture where you see it growing naturally.
You can grow currants and gooseberry shrubs in pots in part shade.
Is there a place a your school you could do a potted garden? It seems to be all the rage at the moment, but someone has to start it.