I have a student who is taking grape cuttings from a local winery and trying to provide them with rooted stock to plant the next year. We haven't been real successful yet but hopefully we will learn from our mistakes! Custom containers could be another idea, have people bring in their pots and we can custom plant them with plants from our greenhouse - your student would be providing the service of designing and planting the pot. I have seen programs where a student builds planters in the shop, plants them and then sells them during the Spring Plant sale. You could also probably keep and cultivate water garden plants over the winter for people. These are ideas I have had, but not tried yet.