I'd like to know what I stand a chance of growing in the Salinas
|There are lots of cool season crops you can grow, including beets, broccoli, cabbage, carrots, cauliflower, garlic, lettuce, onions, peas, radishes and spinach. All can be started from seeds.
As for setting up a hydroponic system in your greenhouse, National Gardening Association has the following webpage with ideas and resources:
Best wishes with your classroom project!